ELSEVIER
Inorganica Chimica Acta 266 (1997) 91-102
Transition metal (Mn, Co) and zinc formamidinate compounds having
the basic beryllium acetate structure, and unique isomeric
:
iron compounds
F. Albert Cotton a,., L.M. Daniels ", L.R. Falvello b, J.H. Matonic ~, C.A. Murillo ~'¢'*,
X. Wang a, H. Zhou ~
a Laboratm),for Molecular Structure and Bonding v.d .~epartment oj' Chemistry, Texas A&M University, College Station, TX 77843, USA
t, Department of Inorganic Chemistry and Aragon Materials Science Institute, University ¢~fZaragoza-C.S,I.C., 50009 Zaragoza, Spain
"Deparmzem of Chemistry. University of Costa Rico, Ciudad Universimria, Costa Rico
Received 31 October 19q6; accepted 13 February 1997
Abstract
Oxidation of Co2(DPhF).~ or hydrolysis of Co2(DPhF) 4 ( DPhF =, N,N'-diphenyiformamidinate ) gives Co40( DPhF)6 ( I ). This tetranuclear
compound consists of an oxygen atom centered in a tetrahedron of four-coordinate Co atoms with a DPhF bridge along each edge of the
tetrahedron. An idealized T,t symmetry is also found tbr zinc, ll, and manganese, 111, analogs. The latter, Mn.sO(DPhF),~, crystallizes in a
disordered fash~.~mso as to appear as two interpenetrating tetrahedra. Two #4-0 tetrairon compounds, namely, Fe40(DPhF)~, (IV) and
FeaO(DBiPhF ~,,., V) (DBiPhF ~ N,N'-bisbiphenylformamidinate) are also described. These molecules are isomers of the Co, Zn and Mn
molecules ~,~ tb:,,t they have the 'tetrahedron' of metal atoms badly distorted by a different distribution of the formamidinate ligands. Two
opposite Fe,~Fe edges are doubly bridged, another two opposite edges are singly bridged and the remaining two edges are unbridged. The
lengths of these three pairs of opposite edges are short, medium and long and the idealized molecular symmetry is only C~. Crystal data for
I.loluene at ~60°C are: lriclinic, space group Pi, a~13.426(3), b~13.491(3), c~22.600(5) A, ot~99.55(3), fl~95.39(3),
~ 111,80(3) °, Z~ 2, For I|, 1,45CoH1o~at ~ O0"C: orthorhombic, space group Pbca, a ~ 23.8113( 8), b ~ 23,406(2), c ~ 30.956(I) A,
Z - 8. For i11i at =. 150°C: Irigonal, space group R3, a -=23.440( I ), c ~ 10.708( I ) A, Z~ 3. For IV. 1.5 toluene at =~00"C: triclinic, space
8roupl'-[,a~ 14oq20(3),b~ 15,53913),t'~ 19.027(4) A,t,~84.63(3),~85.67(3), y~63.30(3)°,Z-~2. (C>1997EIsevierScienceS.A.
Keywords: Transllion illetal colliplexcs; i~orlllainidillalc coinl)lexcs; Dtnuclear complexes; Cry~tal structu~s
I. Introduction
While studying dinuclear compounds of the type
Co..(DPhF),,, n = 3 or 4 I l l , we noticed that exposure of
their toluene solutions to the laboratory atmosphere (for
example, when cleaning the reaction flasks) gave a fast reaction to produce a bright blue color which slowly changed to
give brown solids. The iron analogs behaved differently [ 2 ].
Solutions of the diiron tribridged compl-"x changed to clear
brown then to an intense burgundy and finally gave a tan
intractable solid. The tetrabridged iron compound produced
a burgundy solution and then intractable solids.
A crystallographic study of the blue crystals of the cobalt
compound revealed a tetranuclear core with tbur divalent Co
atoms tetrahedrally positioned about an oxygen atom to give
* Corresponding authors. Tel.: + 1409-845 4432; fax: + 1409-845 935 I.
0020-1693/97/$17.00 © 1997 Elsevier Science S.A. All rights reserved
Pll S 0 0 2 0 - 1 6 9 3 ( 97 ) 0 5 5 3 8 - 2
a structural moiety which is already familiar in inorganic
chemistry. The [M40] 6' core in which the oxygen atom is
at the center of a tetrahedron of divalent ions was characterized for the first time in the so-called basic acetates of beryllium [31 and zinc [41, M40(OAc)6. In these compounds
each metal atom also has a pseudo.tetrahedral arrangement
of oxygen atones about it. Each of the six acetate groups forms
a bridge betw~, a two metal atoms across each of the six edges
el the tetrahe(~'on of metal ions. For M = Zn, other carboxylate derivativ( • have been structurally characterized, such as
the pivalate ar.~l benzoate [ 5 ], and there is a carbamate derivative [61.
To our kntJwledge only two basic zinc compounds are
known in which the [Zn40] ~'~- core is complemented
by nitrogen-donor ligands, i.e. diphenyltriazenate [7] and
7-azaindolate [8]. A few zinc compounds have been characterized in which the bridging ligand is a transition metal
9Z
FA, £)~tton et al. / hwrgamca Chm~ica Acta 266 (1997) 91-102
tri~-chelated species 191 or a dialkylphosphorodithiolate
[ lOl. For the latter a sult'ur-centcred analog is also known
1111.
For cobalt, a tetranuclear oxo-pivalate has b,:,:n described
[ 12] but the structure was inferred only from spectroscopic
data and the unit cell parameters. A search of the Cambridge
Crystallographic Data Base revealed only three compounds
containing the [Co4016+ moiety, namely 7-azaindolate
[ 13 l, 3,5-dimethylpyrazolate [ 14 ] and the transition metal
tris.chelatedfac- [ Ir(2-aminoethanethiolate) a] [ 15 ].
A variation of the structure of [ M40] 6+-containing species is found for magnesium [ 16] and for a large number of
copper [171 compounds of the type M40(/x-X)6'L4,
X~ halide ion and L =donor species, In this type of compound each metal atom is bonded to five ligands, For manganese only a derivative of the latter class is known, namely
[ Mn4(#a-O) l¢,(PPhMe.,)4 ] 1181,
Despite the wealth of known carboxylato axe-manganese
1191 and axe-iron [201 complexes, there are no reported
analogs of the basic beryllium carboxylates. In this paper we
describe the preparation and characterization of the first such
compounds with formamidinate ligands for manganese,
cobalt and zinc.
For iron(ll) we have prepared compounds that are stoichiometrieally the same but structurally different. Instead of
having an essentially regular M,O core with one symmetrical
N=C=N bridge across each of the six Fe,..Fe edges, these
ironoco|,laining molecules possess a very distorted tetrahe°
dron having two opposite Fe,, ,Fe edges bridged by two NC~N ligand~ ( Fe,, .Fe ~ 2,85 A), two F¢,, ,F¢ edges bridged
by only one N=C=N ligand (Fe,.,Fe~ 3.18 A) and two
unbridled edges with Fe,, .Fe-- 3,5 A,
2, I~perlmental
2,i, General procedures
Except where indicated, manipulations were carried out
under an atmosphere of nitrogen using standard Schlenk roche
niques, Samples for spectroscopic characterization we~v.prepared in a Vacuum Atmospheres drybox under an atmosphere
of argon, Toluene and hexanes were purified by conventional
methods and freshly distilled from Na/K alloy under nitroge,n
immediately prior to use, C%(DPhF)~, C%(DPhF)~ and
Fe:(DPhF)~ were prepared according to published procedures [I,21, Preparations of Mn~(DPhF).~ [211 and
ZnCI:tHDPhF)~ 1221 arc given elsewhere, HDBiPhF
(N,N'°bisbiphenylformamidine) was prepared according to
a slightly mt~litied published procedure 123 ].All diner r~a~
gents were purchased from Aldrich Chemical Co, IR Sl~Clra
were obtained as Nujol mulls between KBr plates on a Perkin.
Elmer 16-PC spcctrophotometrr; magnetic susceptibility
measurements were taken on a Johnson-Matthey MSB- I balance; ~H NMR ( 200 MHz) spectra were recorded on a Varian
XL-2OO spectrometer and UV-Vis spectra were recorded on
a Cary 17-D spectrophotometer.
). 2. Preparation of Co40(DPhF)~ (I)
A mixture of CoCI 2 (O.100 g, 0.77 mmoi) and HDPhF
(0.300 g, 1.5 mmol) was refluxed in toluene (20 ml) for 2
h. The solution was then cooled to - 78°(2 and LiOH. H~O
(0.007 g, 0.20 mmol) and MeLi (1.5 ml, I M solution in
THF/cumcne) were added. The mixture was warmed to
room temperature and stirred for a further 2 h, filtered to
remove L~C! and the filtrate evaporated to give a crude form
of I. Recrystallization from toluene/hexanes gave X-ray
quality crystals of I.CTHs. Yield: 0.150 g, 55%, Magnetic
susceptibility: 5.8 BM (2.9/Co). IR (cm~*): 1679(s),
1646(s), 1601(s), 1587(s), 1571(m), 1548(s), 1525(m),
1463(m), 1377(m), 1323(s), 1222(s), 1210(s), 1171(w),
1154(w), 1077(w), 1026(w), 987(m), 928(w), 899(w),
759(s), 728(w), 697(s), 552(w), 526(w). UV-Vis: 630
nm (482 cm ~ t M-1), 590(sh).
2,3. Preparation of Zn40(DPhF)n (!!)
ZnCI2(HDPhF): ( I,O6 g, 2 mmol) was dissolved in toluene (30 ml), and the solution was cooled to -78°C and
methyllithium (4 retool) was added. After stsrring for 2 h,
the mixture was allowed to warm to room temperature and
was filtered with the aid of Collie, The volume of the filtrate
was reduced to 3/4 and a layer of hexanes ( 30 ml) was added.
Air was then allowed into the reaction flask, A colorless
crystalline solid Ibrmed in 4 days, After iilIoring,the solids
were washed wilh hesanes (2 × 15 ml ) and then dried undcr
vacuum to give 0,34 g o f l i (47%), IR (cm ~): 3056(w),
1650(w), 1606(s), 1560(s,br),1486(s), 1340s (hr), 1228s
(br), I178(m), 1080(w), I028(w), 984(m), 930(m),
891(w), 820(w), 755(s), 692(s), 641(w), 563(m),
521(m), 453(w). IH NMR
10H), 8.05 (s, IH).
(C~D¢,): 8 6.65-:7.17 (mull,
2,4. Preparation of Mn~O(OPhF)~ fill)
In a t~picalpreparation,Mn~( DPhF)., (0.30g,0.34 mmol)
was dissolved in toluene (25 ml) and then to the solution
was added a layer of 30 ml of moist but oxygen- free hexanes.
After a week light cream colored crystals were collected by
filtration. They were washed with warm hexanes to yield
0.09 g (37%). No attempt was made to optimize this yield.
2.5. Prepara¢ionof I:c~O(DPhF)~(IV)
MeduMa. A sample of Fo,~(DPhF).~ (0.250 g, 0.36 retool)
was dissolved in 15 ml of toluene and 30 ml of hexanes,
which had been briefly exposed to air, were layered on top of
the solution. After I week crystals of IV- 1.5C~Hs were collected and washed with hexanes. Yield: 0.050 g, 20%. Magrelic susceptibility: 6.75 BM (3.38/Fe). IR ( c m l ) :
I"A. Cottonel all./inorganica ChimicoAcre 266 f !997) 91-102
1594(s), 1538(s,br), 1485(s), 1377(s), 1334(s), 1218(s),
1173(m), 1153(m), 1025(m), 999(m), 981(s), 926(m),
892(w), 834(w), 771(s), 759(s), 729(m), 696(s),
641(m), 615(w), 582(s), 545(w), 528(s), 512(m),
482(w), 455(w), 408(w). UV-Vis: except for a tail of a
UV txansition, there was no distinguishable transition in the
visible region.
Method b. Compound IV was also prepared from the reaction of FeCI2(HDPhF)2 (0.20 g, 0.39 mmol), LiOH-H20
(4 mg, 0.1 retool), and MeLt (0.9 mmol) in toluene (10
ml). LiCI which formed was filtered and the toluene evaporated to give IV. Yield: 0.109 g, 79%.
2.6, Preparation of Fe40(DBiPhF)n (V)
FeCI, (0,10 g, 0.78 mmol) was mixed in toluene ( 15 ml)
with a sample of HDBiPhF (0.56 g, 1.5 mmoi) which contained a small amount of moisture. The solution was cooled
to -780(2 and MeLt (1.5 ml) was added. The mixture was
warmed to room temperature and filtered to remove LiCI. The
filtrate was layered with 25 ml of hexanes and placed in the
freezer. After 2 weeks crystals of V. C6HI4"4.5CTHx were
collected by filtration and washed with hexanes. Yield:
0,025 g, 9%.
2,Z X-ray crysmllography
Crystals of each of I.CTH,, !1.1.45C~Hi4, Ill and
IV, 1.5C7H, were mounted on the dps of quartz fibers and
93
cooled under a nitrogen stream on the diffractometer. Data
for III were collected on a Nonius CAD4 using well-established techniques, including the use of 0-scans for absorption
correction [24]. A Nonius FAST area-detector system provided the data for the crystals containing I, II and IV. Details
of the use of the FAST in our laboratory have been previously
described [ 25 ]. These highly redundant data sets were corrected for Lorentz and polarization effects, but not for
absorption.
In each case the structures were solved by locating a significant number of atoms (the metal atoms and some or all
of the ligand atoms) via direct methods. The remainder of
the ligand and solvent atoms were found in subsequent dif~'eren.~ce Fourier maps. The structures were refined and analyzed using the SHELXTL programs [261. Data collection
and structure refiaement data are summarized in Table 1.
Refinement of the structures of I. C7H8,11. !.45C6H14 and
IV. 1.SCTHs proceeded in a routine manner, with the possible
exception of a site in II apparently containing highly disordered isomers of hexane. Peaks at this site were refined as
partially-occupied atoms of carbon, and refined acceptably,
but no logical connectivity can be ascertained from a calculation of bond distances. The important part of the structure
(Zn40(DPhF)6) is well-ordered.
The structure of Mn40(DPhF)~ ( I l l ) is complicated by
the disordering of the tetrahedral arrangement of the metal
atoms by a pseudo-inversion center at the position of the
oxygen atom, which generates eight partially-occupied Mn
positions at the corncr~ of a or'be. For each tetrahedron of
Table I
Cryslld and sinletu~ nfl|nementdata liarcomplexes I, II, I!1 and IV
Fttriilulii
Spaet~group
o (A)
b ~A)
c {At
~ I °)
(° 5
y t°)
v (A ~)
Z
D,~l~(g em° '~)
~(Mo Kot) (mm ~1)
Dlffractometer
Temperature (°C)
Ri (1> 2o'(1) )
wR2 (I > 2or(I))
RI (all data) ~
wR2 (all data) t,
Weight parameters,a, b '
Goodness.of-fit ( on F z) o
!' CIH,
!1' 1.45Cnlt1,i
III
IV' I,SC1H,
L'..tl l l,lCo.iN i ~O
CNt.,,lolI,li ll~lldN I ~()
f l.I i,-,oMll4N i ~O
(-'.. ~ol 171tFe,tNi fl)
I515.28
1573.84
Pbca
1407.19
R3
i 549,03
P]
23,8113( 8 )
23.406(2)
23.440( I )
23.4.40(I)
14.920( 35
15.539(35
22.600(5)
99.55(3)
95.39( 3 )
30,956( I )
90
90
10,708l I )
90
90
19,027(4)
84,63(3)
85,67( 3 )
I 11.80(3)
3693( I )
90
17253(2)
120
5094.9(65
63.30(35
3921 ( I )
2
1.362
0.938
Nontus FAST
- 60
8
1.227
1.148
Nonius FAST
- 60
3
1.376
0,782
Nonius CAD4
= 150
2
1.312
0,780
Nonius FAST
- 60
0.062
0.134
0.072
0.170
0.029
0.072
0.049
0.120
0.096
O.152
0.062, 13.417
1.094
0,093
0.189
0.091, 57.65
I, 108
0.044
0.077
0.031, 5.964
1.0~I
0,063
O.129
0.076, 2.343
1.067
P]
13,426( 3 )
13,491(3)
"RI =El IFol- IF~I I/~IFol.
" wR2 = [~w( F,,2 - F,2)2/~w( F,,~)2II/2.
w= I/ [0.2(Fo2) + {ap)2+bp, p = [max(Fo ~ or0) + 2(Fc2) l/3.
u Quality-of-fit= [~w( IFo21 - IF~ z I)21(N,,~- Npmme,~,~)] I/2.
94
F,A C),tton etal./hwrganwa Chimica Acta 266 (1997) 91-102
Table 2
Atomic coordinates (× 104) and equivalent isotropic displaceme.nt
parameters (~," × 10t) for Co.,O(DPhF),~(I .C~H,)
X
)'
Co(1)
Co(2)
Co(31
Co(4)
O(1)
Nil)
N(2)
N(3)
N(4)
N(5)
N(6)
N(7)
N(8)
N(9)
N(10)
N(II)
N(12)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(11)
C(121
C(13)
C(141
C(I~)
CLIO)
C(211
C(2~)
C(23)
3151(I)
1679(I)
4139(I)
2275(I)
2769(3)
3409(4)
1805(4)
4509(4)
5379(4)
1825(4)
604(4)
979(4)
1255(4)
2508(4)
4227(4)
4123(4)
3636(4)
2631(51
5407(5)
851(51
863(S)
3528(5)
4167(5)
4332(5)
4739(6)
5~0(61
6157(01
3745(6)
48~(6)
849(~)
67(6)
= 881(71
C(25)
= 319(8)
C(311
C(3~)
C(331
C(341
C($~)
C(36)
C(41)
C(421
C(~)
C(~)
C(4S)
C(46)
C(Sl)
C(521
C(53)
C($41
C(55)
C(~61
Cl611
C(621
C(63)
CffA,)
C(~31
C(f~)
C(?I)
~84(~)
~266(o)
5~31(61
4~47(71
389O(?)
3899(6)
6319(S)
6849($)
~728(6)
8'083(6)
?$42(6)
66?7(5)
1870(51
2460(6)
~48(71
~077~7)
I~00(71
1398(61
~530(51
= 1180(51
~2284(61
=2732(61
=2076(6)
=979(6)
409(5)
.7.
5851( i )
4726( 1)
6527( I )
7244( 1)
6063(4)
728615)
~335(5)
5832(4)
7085(41
47~9~5)
4244,~a)
5117, 5)
6934~ 5)
3800~4)
5146~ ~)
7739-1)
8614 4)
7650(6)
6350(6)
4350(5)
60&~(51
4127(51
8641(5)
7823(6)
7209(6)
7728(7)
8848(8)
9~6(7)
896~(6)
7492(6)
73~0(7)
7478(71
77~8(81
'/917(91
7`/`/6(7)
4646(6)
4759(61
38.~1(71
28O6(7)
2680( 7 )
3599(6)
8088(6)
8584(6)
9597(7)
10114(7)
960?(6)
8604(6)
4783(6)
4272(7)
4343( 8 )
4899(~ )
5411(~)
5354(?)
383.S(61
4338~6)
3893(?)
2987( ? )
2926(.~)
42.94(6)
Ue q a
1981(!)
2S7g( 1)
3313( 1.~
2885( 1 )
2778(2)
1720(31
2008(3)
2067 ( 3 )
2836(3)
1414(31
2102(31
3574( 3 )
3507(3)
3020d 3)
3496~ 3)
3965~ 3)
3269~ ? )
1698~ 3)
2370~ 3)
15521 3)
37331 3)
32911 3)
37991 3)
14461 3)
1076 ~3)
822(4)
949(4)
1322(41
1580(31
1810(4)
217~(41
2018(41
1487(.~)
1108(5)
1~63(41
1676(31
1~38(41
843(4)
869(4)
1305(41
1697(3)
301 !(31
2577(4)
2752(4)
3356(4)
.~786(4)
3617(31
?89(3)
475(4)
= I~(41
-~408(41
oo110(4)
496(4)
1915~41
1921(41
237~(4)
2369(4)
3895 ( 3 )
22( 1)
21( 1)
21 ( 1)
22( 1)
22( ! )
26(!)
26( 1)
23( I )
22( I )
24( ! )
24( I )
26(I)
28( 1)
25( I )
24( ! )
23( 1)
23( ! )
26(2)
23(2)
23(2)
23(2)
22(2)
21(21
29(2)
33(2)
41(2)
45(2)
46(2)
,16(21
31(2)
41(21
~(~-)
62(3)
70(3)
S0(21
25(~)
34(2)
48(21
47(2)
45(2)
33(2)
2.1(2 )
43(21
49( 2
41(2)
30(2)
30(2)
39(2)
5~ 3)
49( .]~
3?(2)
~?(21
35~21
47(21
.47(21
50(3)
38(2)
27(2)
(conr~..ed)
Table 2 (continued)
x
C(72)
C(73)
C(741
C(75)
C(76)
C(81 )
C(82)
C(83)
C(84)
C(85)
C(861
C(91)
C(92)
C(93)
C(94)
C(95)
C(96)
C( 101 )
C(102)
C( 1031
C(104)
C(105)
C(106)
C(III)
C(I12)
C(113)
C(I141
C(llS)
C( 1161
C(I:I)
C( 1221
C(123)
C(1~4)
C(I~.~)
C(1261
C(IS)
C(251
C(351
C(451
C(551
C(65)
C(751
950(6)
411(7)
-663(7)
- 1216(7)
-678(6)
910(61
- 183(61
-528(8)
183(91
1280(81
1641(7)
1903(5)
I :~04(61
1181(81
653(7)
733(7)
1361(61
5322(5)
5864(6)
6931(61
7469(6)
6939(6)
5883(6)
4491(61
3919(61
4285(8)
5221(81
5789(7)
5417(61
3950(5)
~049(6)
5~38(6)
4868(6)
:~480(61
3176(61
7~.~7191
S0~('~)
8975( 141
9077( 171
8~01( 161
7313(13)
6386( | l )
y
3773(6)
3001(7)
2736(7)
3258(8)
4019(7)
7784(6)
7591(71
8386(9)
9349(8)
9542(8)
8753(6)
2637(5)
1987(71
881(81
414(81
1034(71
2168(71
5286(5)
5954(6)
6133(71
5669(7)
5003(7)
4824(6)
7791(5)
6914(6)
6862(8)
766~)(81
8549(8)
8607(6)
9597(6)
10306(6)
11253(6)
I lSIN(?I
I01~32(0)
9880(6)
i261(11)
1707(91
1368(14)
678( 181
l~10(161
469( I01
1557(12)
z
Ueqa
4174(3)
4485(4)
4529(4 )
4237(5)
3920(4)
3763(4)
3684(4)
3935(5)
4279(4)
4387(4)
4119(4)
2856(4)
3278(4)
3111(61
2528(7)
2111(5)
2267(4)
3~99(3)
4270(4)
4466(4)
4100(41
3539(4)
3343(4)
4594(3)
4840(3)
5415(4)
5751(41
5519(41
49,13(31
3060(3)
3141(31
2922(4)
2621(41
2841(4)
~769(3)
l~O(b)
¢~68lS}
718(81
297(t})
= 253(8)
- 328(6)
135(81
34(2)
46(2)
49(2)
62(3)
49(2)
32(2)
48(2)
58(3)
57(3)
58(3)
40(2)
26(2)
45(2)
61(3)
69(3)
64(3)
43(2)
26(2)
37(2)
48(2)
43(2)
39(2)
33(2)
25(2)
33(2)
52(2)
51(2)
49(2)
33(2)
23(2)
32(2)
35(2)
,t0(2 )
35(2)
]1(2)
It9(,I)
?I(:~)
130(61
161 (~t)
139(61
91(41
116(51
"U,,~ is defined as one third of 1h¢Ir~ce of the onhogon~li~,~d{1,~|onset
metal atoms, one unique atom resides on the three-fold axis
and the other on a general position so that the third and fourth
metal positions are generated by the three..tbld axis. Each of
the six bidentate ligands bridge a face of the 'cube'. at least
in the disordered model. It is probable that the positions of
the nitrogen and carbon atoms are actually slightly different
for the two orientations of the metal atoms, but not different
enough to actually be discernable via X-ray diffraction. This
is indicated by the displacement parameters for the nitrogen
atoms, which are slightly more anisotropic than expected for
first-coo~ination-sphere atoms°
The origins! solution of the structure of Mn40(DPhF)6
was obtained in the centrosymmetric space group R3, in
which each metal position was given one-half of the site
occupancy. The structure refined normally, and at conver-
95
F.A, Comm et at/Inorganica Chimica Acre 266 f!997) 91-102
Table 3
Atomic coordinates ( x 104) and equivalent isotropic displacement
parameters (A2× 103) for Zn40(DPhF)¢,(ii, 1.45C~HI,O
x
Zn(I)
Zn(2)
Zn(3)
Zn(4)
O(l)
C(I)
N(I)
N(2)
C(2)
C13)
N(3)
C(4)
N(4)
N(5)
C(5)
N(6)
36511)
47211)
-42611)
-592(I)
-4611)
-259(2)
- 131(2)
-317(2)
-8(2)
142312)
453(2)
-92(2)
-484(2)
110212)
170(2)
123412)
C16)
-151512)
N(7)
N(8)
N(9)
N(10)
C(II)
N(II)
N(12)
C(12)
C(13)
C(14)
C(15)
C(16)
C(21)
C(2~)
C(23)
C124)
C(251
C(26)
C1311
C132)
C(33)
C(34)
C(351
C(36)
C(41)
C142)
C(43)
C(44)
C(45)
C(46)
C(51)
C152)
C(53)
C154)
C(55)
C(56)
C161)
C162)
C163)
C(64)
C(65)
C166)
C(71)
406(2)
-577(2)
19812)
73(2)
-284(2)
-1182(2)
-1326(2)
-808(3)
-956(3)
-600(3)
81(3)
-77(3)
- 26613)
17613)
233(3)
I,t614)
--587(3)
~640(3)
~08t2)
137412)
1879(3)
199113)
1594(3)
1080(3)
~978(2)
~ I069(3)
- 1560(3)
-1972(3)
- 1890(3)
-1400(2)
1327(2)
120113)
140213)
174213)
1864(3)
1660(3)
160212)
191012)
2265(3)
231513)
2003(3)
164412)
864(2)
y
z
4778(1)
383011)
369811)
463211)
4237(2)
5732(2)
5482(2)
5450(2)
4247(2)
4445(3)
4388(2)
4239(2)
4094(2)
4901(2)
2740(3)
391812)
4025(3)
4231(2)
4225(2)
301112)
2996(2)
5762(2)
3570(2)
4545(2)
6015(3)
626113)
6257(3)
5757(3)
601113)
5767(2)
6148(3)
f~49(3~
oyto(3)
5985(3)
5685(3)
4348(3)
4764(3)
4725(4)
4254(4)
3826(4)
3872(3)
4150(3)
4636(3)
4697(4)
4282(4)
3809(3)
3737(3)
5435(2)
5927(3)
6449(3)
6483(3)
.003(3)
5477(3)
346113)
3478(3)
3027(3)
2566(3)
254113)
2990(3)
4441(3)
226611)
156111)
229211)
1584(1)
1928(1)
1921(2)
2289(2)
1552(2)
3060(2)
190012)
2846(2)
787(2)
2873(i)
1940(2)
192012)
1853(2)
197712)
983(2)
1005(i)
155012)
2298(2)
2680(2)
2004(2)
1918(2)
2724(2)
311112)
3458(2)
3030(2)
341912)
!!66(2)
110412)
726(2)
393(2)
444(2)
83112)
3070(2)
3028(2)
3249(2)
3S03(3)
3545(2)
333312)
3125(2)
3373(2)
3604(21
3591(2)
3337(2)
3098(2)
1818(2)
2(H412)
190013)
154013)
1319(3)
145012)
196112)
2340(2)
2443(2)
218213)
180513)
169417~
737~?~
U~q"
25(1)
25(1)
25(I)
24fl)
17(l)
23(!)
2311)
21(l)
2411)
~ (l)
211)
24(!)
21(I)
21(l)
2311)
2211)
2411)
2211)
21(I)
25(I)
24(1)
2411)
22(I)
21(!)
32(2)
44(2)
46(2)
34(2)
42(2)
26tl)
36(2)
46(2)
55(2)
44(2)
33(2)
2411)
3112)
43(2)
58(2)
53(2)
38(2)
26(I)
35(2)
51(2)
52(2)
42(2)
32(2)
24(I)
3312)
46(2)
55(2)
52(2)
40(2)
2511)
3112)
4112)
45(2)
4112)
~0~2)
23(I)
(continued)
Table 3 (continued)
C(72)
C(73)
C(74)
C(75)
C(76)
C(81)
C(82)
C(83)
C(84)
C(85)
C(86)
C(91)
C(92)
C(93)
C(94)
C(95)
C(96)
C(101)
C(102)
C(103)
C(I~)
C(105)
C(106)
C(IlI)
C(112)
C(113)
C(114)
C(115)
C(116)
C(121)
C(122)
C(123)
C(124)
C(125)
C(126)
C(200)
C(201)
C1202)
C(203)
C(204)
C1205)
C(206)
C(301)
C(302)
C(303)
C(304)
C(305)
C(306)
C(308)
C1309)
C1310)
C(311)
C(312)
C(313)
C(314)
C(315)
C(316)
C(317)
C(318)
C(319)
C1320)
C(321)
x
y
z
1383(2)
1832(3)
1775(3)
1275(3)
g!4(3~
- 1043(3)
-989(3)
- 1443(3)
- 1961(3)
-2021(3)
- 1564(2)
102(2)
443(3)
342(3)
4160(3)
4376(3)
4872(3)
5146(3)
4940(3)
4017(3)
3537(3)
3330(3)
3589(4)
4056(3)
4272(3)
2693(2)
2771(3)
2452(3)
2076(3)
2017(3)
2315(3)
2727(2)
2723(3)
2482(3)
2240(3)
2234(3)
2479(3)
3035(3)
2983(3)
2452(31
1971(3)
2012(3)
2541(3)
5003(3)
5492(3)
5949(3)
5930(3J
5451(3)
4995(3)
3942(!1)
3397(3)
2951)13)
2405(3)
2307(3)
2753(4)
3298(4)
4394(5)
4808(5)
2203(4)
3442(3)
5568(4)
6202(4)
6952(4)
6858(3)
6489(4)
6446(3)
6077(3)
7104(4)
6441(3)
6564(4)
6977(4)
6692(3)
4117(3)
5793(4)
7375(4)
4095(3)
751(2)
515(2)
272(2)
266(2)
499(2)
772(2)
510(2)
284(2)
317(3)
578(2)
808(2)
1173(2)
810(2)
438(2)
417(3)
768(3)
!144(2)
2679(2)
3047(2)
3427(2)
3439(3)
3078(2)
2694(2)
1888(2)
1532(2)
1407(2)
1627(3)
1981(2)
2118(2)
2046(2)
1786(2)
1916(2)
2302(2)
2560(2)
2432(2)
5436(8)
5230(3)
5475(3)
5299(3)
4878(3)
4634(3)
4810(3)
4496(5)
4250(5)
4485(4)
5573(3)
4414(3)
4483(4)
5798(4)
5492(4)
555114)
5119(4)
4739(3)
5846(4)
4826(4)
5695(5)
5(47(4)
5272(4)
5297(2)
4291(4)
5695(5)
4828(2)
-109(4)
-450(3)
-357(3)
26.(2)
-65(3)
137(3)
660(3)
985(3)
799(3)
-1412(2)
-1766(3)
- 1968(3)
-1814(3)
- 1466(3)
- 1265(3)
- 1674(2)
-1717(2)
-2048(~
- 2332(3)
-~2293(3)
= 1961(2)
1530{13)
165413)
!87214)
190914)
1728(4)
151014)
1474(3)
130(4)
372(5)
163615)
1823(4)
1944(5)
2173(6)
1053(8)
1519(7)
979(7)
1515(6)
160215)
1348(8)
1872(6)
721(7)
1784(8)
1647(6)
1736(3)
2373(5)
2044(8)
149213)
U~"
30(2)
44(2)
47(2)
41(2)
30(2)
26(1)
38(2)
51(2)
52(2)
43(2)
31(2)
26(1)
36(2)
50(2)
59(2)
51(2)
36(2)
23(I)
36(2)
46(2)
48(2)
44(2)
34(2)
25(I)
34(2)
48(2)
52(2)
42(2)
32(2)
24(!)
29(2)
37(2)
41(2)
38(2)
32(2)
70
70
70
70
70
70
70
100
100
80
80
I00
I00
100
100
100
I00
I00
!00
iO0
100
100
I00
100
100
100
100
(continued)
~:A. Cotton et al. / Im,rganica Chimwa Acta 266 f 1997) 91-102
9~
T ~ k 3 (conunued)
x
C(322)
C(323)
C(324)
C(325)
Ct326)
2905(6)
2737(6)
1787(4)
1457(3)
1176(7)
y
z
U~q"
6806(4)
6291(4)
2601(3~
3573(3)
6814(4)
4557(5)
4356(5)
5252(3)
5156(3)
5664(4)
100
100
100
100
100
* U~ is defined as one third of the trace of the onhogonalized Uu tensor.
gence the value of wR2 (all data) was 0.165. However,
although the arrangement of the ligands is centrosymmetric,
we proposed that there was no reason why the relative occupancies of the two Mn4 tetrahedra should be exactly 50:50,
so the symmetry was lowered ,a the non-centrosymmetric
space group R3, and the relative occupancy of the two group,;
of metal atoms was allowed to refine. The refinement pro.
ceeded without event, and the residuals dropped dramatically,
the final value ofwR2 (0.077) being less than half of its value
in the centrosymmetric space group. The occupancies of the
two groups refined to 0.377:0.623 (2) for Mn( 1,2):Mn(3,4).
The possibility that the crystals might be inversion twins was
investigated, but evidence of such twinning was not found.
Crystals of V. C6Ht4' 4.5C~Hs were also studied, and the
structure was solved and refined. The large Fe40(DBiPhF)~
molecule refined cleanly, including one phenyl group that
exhibits a slight disorder. However. difference maps revealed
~even distinct areas in the interstices apparently containing
highly disor4ered solve~ molecules (toluene and hexanes).
Since the structure and configuration of the main molecule
was ¢1¢~, no additional attempt to m~xlel the disordered sol°
vent regions was made. The dintensions mid contigurati,m of
the Fe~O(=NCN=). core in V are essentially the same as
those in IV *,
Atomic coordinates tbr i, ii, ili and iV are given in
Table~ 2:5, respectively. Important distances and angles tbr
i and II are given in Table 6. Geometric data for III and IV
listed in Tables 7 and 8, respectively,
3, Results and discussion
3, I,
Syntheses
The tribridged dinuclear compound Co:(DPhF)~ reacts
rapidly with atmospheric oxygen to produce a blue solution.
' ~ ' s ~ s of V. C~H,a, 4.5C~H. f ¢ i, Ihe a ~ o c l i a l c sp~c~ group ( ? :
c with ~'~11F a r ~ c r s ~ ~ 34,735(9), h ~ 27,650(9), c ~ 35,254(8) A, ~
113.41(I) ~. V~31083 A ~ ~md Z~8, Refinement of 1651 ~ ¢ r s
with 136=t5 u~ique tiara gave t'~stduals of wR2~0.29. RI ~0.16 (for MI
d~a) ~ 1 wR2~0,~.5, R1-0,10 for the 9023 dala havtlt~/>2(~y(I)),
I ~ t
bond distances ~ Fe(I)..,F¢(2) ~2,818(2), Fe(I),,,F¢(3) ~
3,='ff)9,(2), Fe(t) .,.Fe(4) ~ 3,512(2), Fe(2),,,F¢(3) ~ 3,502(2), Fe(2),,,
Fe(4)~-3,224(2), Fe(3),,,Fe(4)~-2,843(2), Fe(I)-.-O~i,961(6),
F'¢(2)~0 ~- 11966,(6), F¢(3)=0-- 1,955(6), F~(4)=O,= 1,948(6), all
P~-N t,#the I ~ 2,0,g=2,0~A, See also Section 5,
Table 4
Atomic coordinates (X 104) and equivalent isotropic disnlacement
parameters (A 2× 10~) for Mn40( DPhF)6 (llI)
Mn(1)
Mn(2)
Mn(3)
Mn(4)
O
N(1)
N(2)
N(3)
N(4)
C(II)
C(12)
C(13)
C(14)
C(15)
C(16)
C(I)
C(21)
C(22)
C(23)
C(24)
C(25)
C(26)
C(31)
C(32)
C(33)
C(34)
C(35)
C(36)
C(2)
C(41)
C(4))
C(43)
C(4a)
C(45)
C(46)
x
y
3333
2408(I)
3333
4258(I)
3333
2314(2)
-3333
-3864(!)
-3333
-2801(!)
-3333
-4308(2)
- 3754(2)
-2406(2)
-2876(2)
-4835(2)
-5457(2)
-5955(2)
-5848(2)
-5234(2)
-4730(2)
-4194(2)
- 3674(2)
- 3040(2)
-2945(2)
-3475(2)
-4094(2)
=4201(2)
-1874(2)
4734(3)
7189(2)
8368(2)
5922(I)
6547(6)
4458(4)
5406(4)
-1964(2)
10323q4)
11050q5)
10961q5)
10111(5)
9346(5)
8404(5)
7470(5)
73~6(0)
1860(2)
4299(2)
4798(2)
2215(3)
1660(3)
1594(3)
2087(3)
2644(3)
2710(3)
1828(2)
1305(2)
1396(2)
872(2)
246(2)
151(2)
675(2)
4395(3)
3912(2)
3983(3)
4551(3)
5029(3)
4947(3)
4~!8(2)
53S6(2)
~249(~)
57~1(~)
~398(2)
6~11(2)
599~(2)
Z
= 1449(2)
-839(3)
=745(2)
= 1257q 2)
,2474q 2)
= 29~|q 2)
: 3590~2)
=~~715q3)
8689(4)
7601(4~
3662(4)
3736(5)
2961(5)
2117(5)
2058(4)
2832(5)
4625(4)
5568(5)
5630(6)
5837~5)
5993q5)
5917~5)
5701q4)
9472q5)
24.t012)
Ueq a
20(I)
21(I)
18(I)
18(I)
20(I)
32(I)
43(I)
37(I)
44(I)
34(I)
35(I)
46(I)
46(I)
37(!)
34(I)
22(!)
36(i)
50(2)
48(1)
40(I)
35(I)
32(I)
31(I)
32(I)
39(!)
47(I)
47(I)
40(I)
26(I)
35(I)
47(2)
48(I)
7070(5)
7|67(~)
735~(4)
42(I)
31(I)
* U~.4is defined as o,te third of the trace of lhe onhogonali~cd U,~lellSOr,
Comparison of the visible spectra shows that the same species
is formed from Co:(DPhFL, solutions upon exposure to
moisture but the rate of reaction is considerably slower for
the latter, The reactions can b~ descril~d by the following
equations:
2Co~(DPhF).~ + 1120: =* Co~O(DPhF)~
(I)
2Co.,(DPhF) a + H=O ~ Co~O( DPhF)~ + 2HDPhF
(2)
In Eq. (!) an oxidation takes place while hydrolysis is the
process involved in Eq. (2). For synthetic purposes process
(!) gives the best results and the reaction is essentially
quantitative, However, since the preparation of either
Co~(DPhF),, n ~ 3 or 4, is not trivial, we also prepared 1
using a simpler synthetic method by adding a stoichiometric
amount of LiOH Lo a mixture of CoCIz(HDPhF)2 and LiMe
4CoCI:(HDPhF) ~ + LiOH + 9LiMe
-~ Co~O(DPhF)~÷ 2LiDPhF+ 8LiCI +9CH4
(3)
97
F.A. Cotton el aL / hu)rganica Chimica Acta 266 ~1997) 91-102
Table 5
Atomic coordinates (× I(P~ ,'rod equivalent isotropic displacement
parameters ( ~-"x !0 ~) |'or F%O(DPhF), ( IV. I .SC~Hs)
X
Fe(1)
F¢12)
F¢(3)
F¢14)
O(I)
Nil)
N(2)
N(3)
N(4)
N(5)
N(6)
N(7)
N(8)
N(9)
N(10)
N(II)
N(12)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(II)
C(12)
C(13)
C(14)
C(15)
C(16)
C(21)
C122)
C123)
C(~4)
C{2~)
C12~)
C(31)
C132)
C(33)
C(34)
C(35)
C(36)
C141)
C(42)
C(43)
C144)
C(45)
C(46)
C(51)
C(52)
C(53)
C(54)
C(55)
C156)
C(61)
C(62)
C(63)
C(64)
C165)
C(66)
C(71)
7444(!)
6247(1)
8859(!)
7499(I)
7519(2)
6204(2)
5179(2)
7033(2)
6576(2)
8943(2)
9366(2)
5784(2)
5975(2)
8624(2)
8084(2)
9843(2)
8628(2)
5314(3)
6772(2)
9509(3)
5513(3)
8437(3)
9570(3)
6213(3)
6899(3)
6929(3)
6271(3)
5595(3)
5565(3)
4253(3)
3759(3)
2911~ 4 )
~516q ,I)
~00S, ,1)
]87X~,I)
7250~2)
7856~3)
8050q3)
7659~3)
7076~3)
6870t3)
625613)
6833~3)
6474(4)
5553(4)
4976(4)
5336(3)
9263(2)
9275(3)
9543(3)
9818(3)
9809(3)
9531(3)
9906(3)
9369(3)
9863(4)
10878(4)
1141914)
10931(3)
5526(3)
y
Z
U,,q =
1732(i)
3632(1)
2472(I)
2278(!)
2534(2)
1537(2)
3201(2)
2505(2)
4025(2)
816(2)
2086(2)
4327(2)
2881(2)
3636(2)
3009(2)
129812)
906(2)
2299(3)
3442(3)
121913)
3836~3)
3592~3)
71413)
62813)
18913)
107913)
1162q3)
35713)
540q3)
39064 3 )
48()3q 3)
55()9~3 )
534114)
,t456(4)
37461~)
1958(2)
2038(3)
147613)
826(3)
735(3)
1290(3)
5028(2)
5463(3)
6459(3)
6990(3)
6557(3)
5574(3)
- 180(2)
~475(3)
= 1443(3)
=2105(3)
-1812(3)
- 851(3)
2~04(3)
334113)
3782(3)
3402(4)
2582(4)
2132(3)
5303(3)
1823(I)
2278(!)
2488(1)
3552(1)
2527(!)
2174(2)
2068(2)
872(I)
1274(2)
1621(2)
1470(2)
3208(2)
3788(2)
3040(2)
4058(2)
3086(2)
3670(2)
2126(2)
763(2)
1324(2)
3714(2)
3732(2)
3496(2)
2388(2)
2072(2)
2268(3)
2783(3)
311113)
291912)
178712)
2073(3)
1768(3)
110813)
910(3)
1201(2)
267(2)
299(2)
868(2)
=875(2)
= 312(2)
2~9(2)
108012)
123712)
1097(3)
81013)
662(3)
788(2)
1502(2)
844(2)
755(2)
1327(2)
1986(2)
2080(2)
1032(2)
612(2)
188(2)
182(3)
598(3)
1025(2)
3328(2)
25(1)
28(1)
28(1)
26(1)
26(1)
30(!)
31(!)
28(I)
29(I)
29(I)
28(I)
29(I)
29(I)
3411)
3211)
3411)
2811)
32(I)
2911)
29(I)
3111)
3311)
30(I)
3011)
3911)
5811)
6311)
54(I)
3811)
3911)
5311)
72(2)
?7(2)
8l(2)
5911)
2911)
37(I)
4611)
4911)
4811)
3411)
3011)
4311)
6311)
72(2)
68(2)
50(I)
2811)
36(!)
45(I)
49(i)
47(I)
37(I)
32(!)
39(!)
55(I)
68(I)
78(2)
52(i)
33(I)
(cwat#med)
Table 5 (continued)
C(72)
C(73)
C(74)
C(75)
C(76)
C(81)
C(82)
C(83)
C(84)
C(85)
C(86)
C(91)
C(92)
C(93)
C(94)
C(95)
C(96)
C(IOI)
C(102)
C(i03)
C(104)
C(105)
C(106)
C(IIi)
C(112)
C(I13)
C(114)
C(115)
C(ll6)
C(121)
C(122)
C(123)
C(124)
C(125)
C(126)
C(IS)
C(2S)
C(3S)
C(4S)
C(5S)
C(6S)
C17S)
C(8S)
C(9S)
C(10S)
C(IIS)
C(12S)
X
y
,7
5596(3)
536414)
5062(4)
5Oi3(3)
5234(3)
5426(3)
4420(3)
3906(3)
4397(3)
5402(3)
5923(3)
8727(3)
8105(4)
8209(5)
8895(5)
9510(4)
9426(3)
8180(3)
9096(3)
9194(4)
8390(4)
7476(4)
7377(3)
10884(3)
11538(3)
12560(4)
12912(4)
12261(5)
11255(3)
8464(2)
8648(3)
8423(3)
802113)
783113)
8050(3)
1286115)
972(7)
1201118)
1448(16)
2020116)
1951(9)
1315118)
14948117)
14010(13)
14773110)
14273(8)
14469(6)
5569(3)
6522(3)
7215(3)
6947~3)
6003(3)
2409(3)
2717(3)
2245(3)
1455(3)
1135(3)
1608(3)
4463(3)
5369(3)
6167(4)
6066(4)
5172(4)
4367(3)
2850(3)
2565(3)
2375(4)
2449(4)
2717(4)
2914(3)
988(3)
46(4)
- 213(5)
489(8)
1400(6)
1666(4)
192(2)
89(3)
=548(4)
-1089(3)
= 980(3)
-334(3)
4046113)
3901110)
4213117)
4870(21)
4908(17)
461~(10)
3710113)
=24(19)
1123113)
322111)
940(8)
58117)
3992(2)
4085(3)
3536(3)
2S79(3)
2765(2)
4149(2)
4038(2)
4395(3)
4851(3)
4955(2)
4611(2)
2738(2)
2961(3)
2662(4)
2125(4)
1888(3)
2194(2)
4807(2)
5103(2)
5824(2)
6259(2)
5964(2)
5248(2)
2943(2)
2795(2)
2673(3)
2681(3)
2806(3)
2936(2)
4123(2)
4837,2)
5273q2)
500512)
430412)
3857i2)
4807t9)
4223(I)
3%0115)
~559(25)
3900(25)
4058(13)
5420(13)
=935111)
5112)
370(8)
837(9)
=410(6)
Uo4 a
43(I)
56(!)
60(1)
54{1)
43(1)
31(1)
42(!)
55(i)
56(I)
49(I)
37(1)
37(!)
57(1)
87(2)
89(2)
67(I)
47(I)
34(i)
46(1)
62(I)
64(I)
63(!)
48(I)
40(1)
58(!)
88(2)
108(3)
90(2)
62(!)
30(!)
44(I)
58(I)
54(I)
49(I)
37(I)
241(12)
154(5)
266( ! I )
332(20)
352(26)
214(11)
3~(15)
12i(8)
109(5)
72(3)
153(4)
10112)
"U,.,, is definedas one third of t11¢trace of the orthogonalizcd Uu tensor,
Compound I is relatively stable in air both in solution and in
the solid state; it decomposes slowly to produce a brownish
solid.
Hydrolysis also explains the process that leads to the fi)rmation of Zn40(DPhF)c,, which forms upon exposure to air
of toluene solutions of Zn:(DPhF)4, made by reacting
ZnCI2(HDPhF): with methyilithium, as follows:
2ZnCI: (HDPhF): + 4LiMe
toluene
Zn2(DPhF)4 + 4CH4 + 4LiC!
(4)
F.A. Cotton et al. / lnorganica Chimica Acta 266 (1997) 91-102
9~
Table 6
S~le~.~datom ~pafallom (]k) and bond angles (o) forCo40(DPhFh, and Zn~O(DPhF)~
M=Co
M=Zn
M( I)...M(2)
M( I)...M(3)
M{ I)...M(4)
M(2)...M(3)
M(2)...M(4)
M( 3).. oM(4)
M(2)-4:)( I )
M(3)-O( I)
M( 4)~4)( I)
M( 1b4)( I )
M( I )=N( I)
M(I)~N(3)
M(I)=N(5)
M(2)=N(6)
M(2)~N(7)
M(2)=N(9)
M(3).-N(4)
3.141(2)
3.015(2)
3.147(2)
3.227(2)
3.184(2)
3.128( I )
1.920(4)
1.925(4)
1.929(4)
1.925t 5)
2.033(5)
2.022(5)
2,003(6)
2.(}08(6)
2.002(6)
2.001(5)
2.044(5)
3.122( I )
3.153( I)
3.1272(9)
3.1278(9)
3.1554(9)
3.122( I )
i.927(3)
1.919(3)
1.920(3)
1.912(4)
2.030(5)
2.023(5)
2.045(4)
2,037(4)
2,028(5)
2.024(5)
2,029(5 )
O( I)=M( I )~N( I )
O( I )=M( I)=N(3)
O( I)=M( 1)=N(5 )
N( I)=M( I )=N(3)
N( I)=M( I )~N(S)
N(3) °M( !)=N(5)
O( I ) oM(2)=N(6)
O( I)=M(2)=N(7)
O( 1)=M(2)=N(9)
N(6)=M(2)=N(7)
N(6)=M(2)=N(9)
N(7)=M(2)=N(9)
O( I)=M(3)=N(4)
0(1 )=M( 3)=N(I0)
O( ! )=M( 3)=N( I I )
N( 10):M( 3 )=N(4)
N( II )=M(3)=N(4)
N( 10):-M(3):-N( I1 )
O( 1)=M(4)=N(2)
O( 1)=M(4)=N(8)
O( i)=M( 4)=N(12)
N(i~)=M(4):N(2)
N(12)=-M(4~=N(2)
N(8)o.M(4)=N(12)
104.7(2)
I07.4(2)
I07,8(2)
112,6(2)
I05,5(2)
118,1(2)
102,9(2)
107,0(2)
!04,0(2)
I09,0(2)
117,6(2)
lIS,0(2)
109,I(2)
I0~,6(2)
103 3(2)
103,6(2 )
I I 1,0(2)
122,6(2)
103,9(2)
[0~,~(: )
IES,I(2)
124,0(2)
108,2(2)
108,6(2)
105.0(2)
~0~t0(2)
105,2(2)
I13,2(2)
113,7(2)
114,4(2)
I05,0(2)
104.0(2)
105,8(2)
114,$(2)
113,0(2)
113,S(2)
104,6(2)
I05,2(2)
104,9(2 )
I13,7(2 )
113,3(2)
1139(~)
10~,~(2)
104,6(2 )
I04,5(~)
11£3(2)
113,3(2)
114.0(2)
2Zn: (DPhF L, + H:O ~ gn~O(DPhF)~ + 2HDPhF
(5)
Support for Eq, (4) is provided by ~H NMR data, 'rh¢
hydrogen atom of the methinc proton in Zaa(DPhF)4at 8,20
ppm quickly disappears upon addition of one equivalent of
water and the data clearly show the presence of both compounds, It and HDPhE in a I to 2 ratio, Two n,~w singl~ts
appear at a 8 value of 8,05 ppm (for l) and 7.87 ppm (for
HDPhF), The signal corresponding to the neutral (proton°
ated) ligand does not appear after the solid has heen washed
with warm hexanes,
As indicated e~rlier, the. reactions of the ir~m ~nalogs are
more complex, The easy access to higher oxidation states
promotes the formation of soluble ~nd insolubie oxo. and
hydroxoqron compounds, We have already show~ that in the
presence of ~ir, iro~ solutions which canton lithium formamidinate speci¢~ are readily oxidized to give intensely colored
solutions conlaining an unusual iron-oxo tetranuclearspecies,
M=Co
M=Zn
M(3)-N(I0)
M (3)-N( 11 )
M(4)-N (2)
M(4)-N(8)
M(4)-N(12)
N( 1)-42( I )
N(2)-C( I )
N(3)=C(2)
N(4)-C(2)
N(5 )-C(3)
N(6)-C( 3 )
N(7)--C(4)
N(8)~C(4)
N(9)--C(5)
N(10)-C(5)
N( 1 I)-42(6)
N(12)-42(6)
2.017(5)
2.020(6)
2.060(6)
2.039(6)
2.043(6)
1.310(9)
!.340(9)
1.322(8)
1.335(9)
1.306(8)
1.332(8)
1.326(9)
1.317(8)
1,322(8)
1.317(8)
1.314(8)
1.323(8)
2.028(5)
2.031(4)
2,027(5)
2.029(5)
2.040(4)
1.318(7)
i.325(7)
1.324(7)
1.324(7)
1.318(8)
1,321(8)
1.333(7)
1,338(7)
1.312(7)
1.333(7)
1.331(8)
1.310(8)
M( I )-43(I)-M(2)
M( I)-O( I)-M(3)
M( I )-4)(I )-M(4)
M(2)-O( I )-M(3)
M(2)-O( I )~M(4)
M(3)=O( I )-M(4)
C( I)-N( 1 )-M( I )
C( I)~N(2)-M(4)
C(2)=N( 3)=M( ! )
C(2 )=N(4)=M(3)
C( 3)=N(5)~M( I)
C( 3)=N(6)=M(2)
C(4)=N( 7)=M(2)
C(4)=N(g)=M(4)
C( S )=N( 0 )=M( 2 )
C( S )=N( I0 )=M( 3 )
C(6) :N( 11 )=M(J)
C(6}-N(12)-M(4)
N( ! )--C( I )=N(2)
N( .t)-[?.( 2)-N(4 )
N( $ )-~( 3 )=N(6 )
N(8)=C(4)=N(?)
N(10)=C(S)=N(9)
N( I I)~C(6)~N(12)
109.6(2)
103.1(2)
109.5(2)
114.1(2)
I11.7(2)
108,5(2)
119.6(4)
113.7(4)
116,2(5)
115.5(4)
125,0(5)
125,7(4)
125,6(5)
129,2(5)
127 8( ~ )
128,7(4 )
I I?,0(S)
i 17,8(4)
1~9(6)
121.4(0)
1263(6)
127,6(7)
I~.~S(6)
121 .$(?)
108.8(2)
II0.8(2)
109.4(2)
108.8(2)
110.2(2)
108.9(2)
117.6(4)
117.6(4)
118,1(4)
117.0(4)
115.4(4)
116,5(4)
118A(,l)
116,7(4)
II?,3(4)
I17,2(4)
1100(4)
117,3(~t)
12,1:1(~)
I ~.1.9(~ )
i24 ?(5)
122,?(~)
123.9(5)
123,1(.S)
namely, Li:(HDPhF):Fe~O~(DPhF)~. which has an eight°
mombered ring of alternating iron and oxygen atoms [21.
Under controlled conditions, exposu~ of air to solutions
of the very air-s~nsitiv~ F~2(DPhF)~ compound gives less
intensely colored solutions from which Fe~O(DPhF)~, crystals can be isolated according to
2Fe.~(DPhF).~+ I/20~ ~ Fe~O(DPhF)~
(6)
We have also prepared IV from a procedure analogous to
that :dlownin Eq, (3) using F~Ia(HDPhF) ~as slardng material. A similar product is isolated from the rcaclion of
FeCi~(HDBiPhF)~ and LiMe in the presence of a small
amount of moisture:
2F¢Ci~(HDBiPhF)a + H20 + 8LiMe
Fo,~O(DBiPhF)¢, + 2HDBiPhF + 8CH4 + 8LiCI (7)
F.A. Cotton et al. I hmrga.ica Chimi('a Acre 266 ¢19971 91-102
Table 7
Selected atom separations (A) and bond angles (°) for Mn.=O(DPhFb,.
Atoms Mn( ! ) and Mat2) represent one of the two disordered systems,
Mn(3) and Mn(4) 1he other
Mn( I )...Mn(21
Mn(2).-.Mn(2)'
Mn(3),.-Mn(4)
Mn(4),-,Mn(4) =
Mn( 1 )-O
Mn(2)-O
Mn(3)-O
Mn(4)-O
Mn( I )-N( I )
Mn(2)-N(2)
3.235(3)
3.264(31
3,225(2)
3,262(2)
1,942(7)
2.006(3)
1.949(7)
1.999(2)
2,358(5)
2.386(5)
Mn(2)-N(3)'
Mn(2)-N(4)-'
Mn(3)-N(3)
Mn(4)-N ( 1 )~
Mn(4)-N(2) ~Mn(4)-N(4)
N(I)-C(I)
N (2)-C( ! )
N(3)-C(2)
N(4)-C(2)
2.089(51
2.146(4)
2.246(5)
2.112(4)
2,145(4)
2.256(5)
1,305(6)
1,301 (6)
1,325(6)
1,304(6)
N(I)-'LMn( I ) - N ( I )
O=Mn( I )~N(I)
O-Mn(2)=N(2)
O-Mn(2)-N(3)'
O-Mn(2)-N(4) ~
N(3) LMn(2)-N(4):'
N(3)LMn(2)-N(2)
N(4):'-Mn(2)-N(2)
O-Mn(3)-N(3)
N(3)LMn(3)=N(3)
O-Mn(4)-N( I )'
O=Mn(,I)=N (21"
N( I )LMn(4)~N(2) ~'
O-Mn(4)=N(,I)
N( I ) '=Mn(4)=N(4)
118.46(5)
97.2(I)
97.6121
102,4(21
102,8(21
117.7(2)
111.9(21
119.8(2)
98,8( I )
117,70(7)
103.8(21
106!( ! )
116.3(21
99.2(2)
109.2(2)
N(2):-Mn(4)-N(4)
Mn(l)-O-Mn(2)
Mn(2)~'=O=Mn(2)
Mn(3)~O=Mn(4)
Mn(4)'-O-Mn(4)
C( i )-N{ l )-Mn(4)-"
C(I)-N(i)-Mn(I)
C( I)-NI2)=Mn(4)'
C( ! )=N(2)-Mn(2)
C(2)=N(3)=Mn(2) z
C(2)-N(3)=Mn(3)
C(2)~Nt4)=M,(2) t
C(2)=N(4)~Mn(4)
N(2)=C( I )-N( I )
N(4)=C(2)=N(3)
119.3(2)
i =u.O(2)
108.9(2)
109.6(2)
109.4(21
122.7(31
110.5(3)
119.7(3)
104.4(3)
!19.0(41
113,4(3)
! 18,0(3)
109,0(31
122.7(5)
120,9(51
Synlllielry trallsfornlations llsed to generate equivalent alotns: s =y.
I-o=v~ I. :; ~ ~x +y + I,=X, ;'.
Further reaction el' the iron complexes with oxygen gives the
¢hm'acleristic burgundy color of the oxidized material which
quickly gives rise to intractable tan solids upon exposure to
IIIOIV ilif,
The |'eaclivily of mangm~es¢ compouml:; is similar to thai
o1"the il'OncL.nl-~!cxes.A h.°L~eillllll|l~r t)l' i)gl)~ lllld hyth'oxomanganese species are known in various oxidation states, but
carcthl hydrolysis of MIb(DPhF)4 provides an almost col°
orless divalent oxooccnlcrcd letramanganese cotnpound
according to
2Mn:( DPhF),~ + ioi~O=} Mn40(DPhF). + 2HDPhF
(8)
This compound is very sensitive to air and decomposes
quickly to give a dark (almost black) ivsolublc matcrial.
3.2. Str.ctural co.sidera,ions
The structure of both ! and II, shown in Fig. I, is similar
to that of Ihe basic zinc or beryllium carboxylates. It consists
of an oxygen atom at the center of a tetrahedron of metal
atoms. Each metal atom is tetrahedrally coordinated to the
central oxygen atom and to three nitrogen atoms from three
independent DPhF groups. Each iigand forms a bridge to
each of the other three metal atoms along the edges of the
[M401 f'' unit as seen in Fig. 2. The tetrahedron o1" metal
atoms is quite regular for the Zn compound, for which the
non-bonded Zn...Zn distances vary from 3.122(I) to
99
Table 8
Selected atom separations (A) and bond angles ( ° ) for Fe.=O( DPhr: ),~
Fe(I)...Fe(2)
Fe( I )--.Fe(3)
Fe( I ),,.Fe(4)
Fe(2)--.Fe(3)
Fe(2).- -Fe(4)
Fe(3)-.-Fe(4)
Fe(I)-O(!)
Fe(2)-O( ! )
Fe( 3)-O( ! )
Fe(4)-O( ! )
Fe(I)-N(I)
Fe(I)-N(3)
Fe( I )-N(5)
Fe(2)-N(2)
Fet2)=N(4)
Fe(2)=N(7)
Fe(3)-N(6)
2,857(!)
3.197(I)
3.489( 1 )
3519( i )
3.160(2)
2.850( I )
i.953(2)
i.952(21
!.953(2)
!.955(21
2.059(3)
2.048(3)
2.070(3)
2.062(3)
2.044(3)
2.067(3)
2.065(3)
Fe(3)-N(9)
Fe(3)-N(! I )
Fe(4)-N (8)
Fe(4)-N(10)
Fe (4)-N (12)
N( ! )-C( ! )
N(2)-C(I)
N(3)-C(2)
N(4)-C(2)
N(5)-C(3)
N(6)-C(3)
N(7)--C(4)
N(8)-C(4)
N(9)-C(5)
N(101=C(5)
N(II)-C(6)
N(12)=C(6)
2.057( 3 )
2.058( 31
2.064(3)
2.051(31
2.044(3)
i.327(51
!.319(51
!.326(41
1.317(41
!.327(51
1.321(51
1.325(51
!.325(51
!.328(51
1 326(5 )
!.323(51
1.321(41
O(
O(
O(
O(
O(
O(
102.7( I )
110,7( I )
102.3( I )
1119(I)
I01,5( I )
102.5( I )
102,5( I )
101,9( I )
111,8(I)
101,2( )
112.4( )
101,7( )
103.8( )
134,6( )
102.0( )
0~kS( )
106,9( )
I :~4 (l()
133,9( )
102 2( I
I04.2( )
107,7( )
133.3( )
100,2( )
Fe( I )-O( I )-Fe(2)
Fe( I )-O( ! )-Fe(2)
Fe( 1 )-O( I )-Fe(4)
Fe(2 )-O( I )-Fe(3)
Fe(2)-O( ! )-Fe(4)
Fe( 3)=O( i )-Fe(4)
C(I)=N(I)=Fe(I)
C( I )-N(2)-Fe(2)
C(2)=N(3)=Fe( I )
C(2)=N(4),°Fe(2~
C(3)-N(5)-Fe( I )
C(3)-N(6) Fel3)
C(4)=N(7)=Fe(2)
C(4)-N(8)~Fe(4)
C(5)~N(9)-Fe(3)
C(5)--N(10)=Fc(4)
C(e,)~ N( I I ).-F~,(~)
('{61 N( 12)--Fc(41
N(2) ,C(1)-N(I)
94.0( I )
109.9(I)
126.5( I )
128.0( i )
107.9( I )
93.6( I )
!17.4(21
124.5(2)
124.6(21
120.3(2)
116,7(21
116.2(2)
112.9(2)
114.6(2)
1185,21
124 2(2)
12~ ~112)
121 2(21
124 I(~)
N(e,) C('~) N(5)
N('/)=CI4)-N(8)
N' 10)=C(5) ~N(O)
N( 12)~ C ( 6 ) - N ( I I )
1220(~)
121K('~)
12~,7(~)
1240(~)
I )-Fe( I )-N( i )
I )-Fe( I )=N(3)
I )-Fe( ! )-N(5)
I )-Fe(2~=N(2)
1)-Fe(2)-N(4)
I )-Fe(2)=N(7 ~,
O( I 1 ~Fc(3) =Nt6)
O( I )=Fe(3)=N(9)
O( I )-Fe(3)=N( II )
O( I )~ Fe(4)-N(8)
O( I )=Fc(4)-N(I0)
O( I )-Fe(4 )-oN(12)
N( I )=Fc( I )-N(3)
N(i)=Fe(I)=N(5)
N(3) 4~e( I)~N(51
N(21- Fc(2)~N(4)
N(21- Fe(2)-N(7)
N(,I )-Fe( 2 )--N( 7)
N16).d:e(3)=N(9)
N((~) I:e(~) N ( I I )
N(0) Fc(~) N ( I I )
N(8)=Fe(4)=N(I0)
N(8)=Ft~(4)=N(12)
N(I(I).°R~'(4) =N(12)
3. ! 53( ! ) ,~, but it is slightly more distorted in the Co comt~lex
(the Co...Co distances vary from 3.015 ( 2 ) to 3,227(2) ,~ ),
However, those distances are about the same as those tk~und
in the carboxylate analogs I ! 21. The M=O distances of 1.92=
!,93 .,~ for I and i,9111,93/~ for 11, respectively, are also
those expected for this type of metal core, as are the Iv-N
distances. The M=N distances are regular, but the Co=N di,~tances are ~ 0.08/~ longer than those tbund in the dinuclcar
species Co2(DPhF),,, n = 3 or 4. It is worth noting the high
degree of flexibility provided by the formamidinate ligaads.
In many dinuclear complexes the ring is essentially planar,
but in compounds in which there is a long M...M distance
the I~-ZNLCL~NL~Mdistortion from planarity is very significant. As can be seen in Fig. 2, for the zinc compound lhere
are two planar moieties (gn( I ), N(3), C(2), N(4), Zn(3)
and Zn(2), N(71, C(41, N(8), Zn(4) ) and four non° planar
rings distributed in a regular manner about the metal atoms.
100
F.A Cotton et al.
I
Inorganica Chimica Acta 266 (1997) 91-I02
N(81
N(2)
CI92)
C|25l("'~
C[1111
Nr
C(61l
N(5) ~
.....
1041
C:1531
..... ~/ '
Cl33)
C15~
Fig. 3, A drawing of the co~ in com~und II showing the unsymmetrical
distribution of the plan~ ~ d twisl~ Co=N~C=N=Co groups.
Fig I. Therm$ ellipsoid plot of the Zn~O(DPhF),~ molecule. The atom
bbeling scheme is the same in the Co analog, Atom,~ are represented by
their 40% probability ellipsoids, Numhe=mg for phenyl carhon atoms proceed~ logically from the numbers shown.
NI4~
Ft[~ 4 Keprc~cJ~lalhm of tltc di~(mie~' ~| Ih~ ¢olx, ol |h~ Mth~)(lTPhi~)~
molecule Oae Ot~Cnlati~llt', t~p|~,~cnlcdby ~)lid bo.d~. |he olht~l by oI~.
bond~,
Fig, 2. A d¢~wing of the core in compounds I showing the ~etral~dral
arxa|Igement of the me[~l ~toms about ~be centr~l oxygen ~nd th~ ~gul~r
distributionof DPhF llgands.
Thc conformation is different in the cobalt compound. As
shown in Fig. 3, there are thre~ bridges ofeach type present.
In spite of the relative similarity in the metal~metal distances
in I and II the distribution about the Co atoms isnot e0gul~,
Atom Co(2) is connected to planar bridges exclusively while
each of the remaining Co atoms connect to a planetand two
twistedCo=N=C=N=Co groups,
The structure of III is also similar to that of ! and il with
the additional complication of crystaUogr~phic disorder of
the metal atoms. There are two possible orientations of the
tetcahedton foiTncd by the t~ur Mn atoms, The two orient;ltions arc related by a pseudo-inversion center Iocaled at the
position of the oxygen atom as indicated in Fig. 4. The anisotropic displacement parameters (ADPs) of the ligand
atoms drawn in Fig. S show subtle but convincing evidence
that the disorder is not limited simply to the occupation of
two sets of sites for the manganese atoms. The ADPs of all
of the ligated nitrogen atoms, as seen in visual inspection of
their 'thermal dlipsoids', indicat,~"an unusual elongation that
cannot reasonably b¢ atbibuted t~ thermal motion. There are
two crystallographically independent formamidina|c ligands,
with a total of four nitrogen atoms. Each nitrogen atom is
bonded to one manganese atom of each of the two disordered
congeners, and for every nitrogen atom the two congeneric
Mn-N distances arc significantly difl~rcnt. The thermal ellipsoid in each case is elongated and tilted in such a fashion that
the axis of largest principal displacement points roughly
toward that manganese congener which is farther from the
nitrogen atom under consideration. These two effects - - the
F A. Cemm eta/,/btergmffca Chimic~aActa 266 ¢!997) 91-102
101
C(6~
CI5~
"~ CI1)
Ni2!
C141
_F
MnI4B)
j
~
~
NIS)
MnI4AI
Fig. 5. A drawing of a disordep~d Mn-N-C-N-Mn group in compound !!1
showing the elongated displacement ellipsoids of the nitrogen atoms.
significant difference between chemically equivalent distances and the elongation of the displacement ellipsoids
taken together indicate that the disorder that is evidenced
principally by the presence of two different sets of sites for
the manganese atoms, is also present in the ligands, but to a
sufficiently lesser extent that the disordered atomic sites
remain unresolved. It is proper, then, to regard all of the MaN distances derived from the crystal structure as 'apparent
bond distances', as discussed in a different context by Stebler
and Burgi [ 27 l, and not as values that have the sort of reliability normally associated with the results of diffraction
analysis. As far as we know this is the first manganese compound which has a structure derived from the basic zinc or
beryllium carboxylates.
Compound IV, whose structure is shown in Fig. ~, ~,',, an
arrangement o1"Fe, O and N atoms which is only partly similar
~~
(~
CI231
~3et2~D
, \qJ
b
C(II
Fig. 7, A drawingo[ thecorein compoundsIV andV.
to that of the Co, Mn and Zn compound described above.
There is an oxygen atom in the center of a highly distorted
tetrahedron of Fe atoms. As in I, 11 and Ill each of the metal
atoms is bonded to the oxygen and to three nitrogen atoms.
However, the formamidinate bridges are not regularly distributed; as shown in Fig. 7. Two of the edges of the tetrahe&on of metal atoms are 4~ubly-bridged, two are
singly-bridged and the other two are non-bridged. The pattern
of non-bonded Fe-Fe distances clearly shows the effect of
such distribution. There are two short distances ( ~ 2.85,3,),
two intermediate ( ~ 3.17 A) and a pair of longer distances
( ~ 3.50/~). Tile bonded Feo43 and Fe-N distances are quite
rcguh,' and show only minor deviations from thc average of
1.95 and 2.05 /~, respectively. The overall idealized sym°
merry of the molecule is C2. Tile structure of compound V is
very similar to that found in IV. As far as we know these are
the first oxo compounds of iron in which the (/x4°OFe4)"'
core has been found.
For IV, the room temperature magnetic susceptibility of
6.75 BM (3.38 BM per iron containing unit) is well below
the typical range of 5.0=5.6 BM per iron unit found in
mononuclear tetrahedral Fe(ll) compounds. This is indica°
live of possible coupling between the electrons. The situation
is similar in the Co analog. Unfortunately the lack of variable
temperature magnetic susceptibility instruments in our laboratory impeded further magnetic studies.
"l )
4. C o n c l u s i o n s
C1112~9
Fig. 6. A plot and labeling scheme of the structure of Fe,sO(DI)hF),. Atoms
are represented by their 50% probability ellipsoids. Numbering for phenyl
carbon atoms proceeds logically from the numbers shown.
Hydrolysis of dinuclear tbrmamidinate compounds of Zn,
Co, Mn and Fe produces oxo-centered tetranuclear coin°
plexes of formula M40(formamidinate)6. Their structures
are related to that of basic beryllium acetate, Be40(OAc)~,.
However, there are small but significant structural differences
in the new family of compounds. The zinc complex is regular.
Each metal atom is bridged by three formamidinate groups
which form two twisted M-N-C-N-M moieties and a planar
102
F.A. Cotton et al. I lnorganiea Chimica Acta 266 (1997) 91-102
F
.,
" ~
".
(a)
(b)
Fig. 8. A schematic representation of the cores in (a) M40(DPhF)s,
M ~, Mn, Co and Zn; (b) the iron analog. Note the differences in the distribution of the DPhF g~XOUl~.Dotted lines indicate singly-bridgedtetrahedron
edg,~, halched line~ reliant doubly.bridged edges and wavy lines are
d~wn for non=bridgededges.
one. The cobalt complex is slightly more distorted with three
planar and three distorted M-N=C-N-M groups of atoms.
All planar groups are bonded to the same cobalt atom. The
manganese complex is qualitatively similar but there exists a
crystallographic disorder in which two independent Mn~O6 +
totrahedraappear to be intertwined. The iron complexes differ
even more. Two F~Fe edges of the tetrahedron are doubly
bridged, another two opposite edges are singly bridged and
the remaining two edges are unbridged. The differences in
the ligand distribution is shown schematically in Fig. 8.
$. Supplementary material
Tables of crystallographic data including bond lengths,
bond angles and anisotropic displacement parameters (70
pages) are available t~om author F.A.C. on request.
Acknowledgements
We ate grateful to the Vicerrectoffa de [nvestigaci6n
U.C.R. (Project 115-8%$16) and the Department of Chemistry for support of work at the University of Costa Rica, the
National Science Foundation for support of work at Texas
A&M University and the Comisi6n lnt~.rministc.,qalde Cienciay Tecnologfa (Spain) (PlDjlect PB95-0792) for support
of work at the Uni~rsity of Zaragoza
References
[I l In) F.A, Colton,LM, D~t¢ls, D J, M~lon~y ~ CA. Murillo, lnorg
Chlm. Act~, 2,19 (1996) 9; (b) F.A. Cotton, L.M. Danlds, DJ.
M~Ioney, J.H. Malonic and C.A. Mudllo, tno~. Chlm. Act~ 256
(1997) 2t~3; (¢) F,A, C~tton, L,M, [.)~tels, X, Fe~, DJ, Malon~y,
L|t. M~ont~ ~d CA, MuSlin, l n ~ , Chim, Act~, 256 (1997) 291,
[ 2] (a) FA. Cotton, LM, D~ieis, L,R, F~lvello and C,A, Murillo, Ino~,
Chtm, Act~, 219 (19~4) 7; (b) F,A, Cotton, L,M, i~mlel,s, UR,
F~l~llo, J,R M~onic ~ ! C,A, Murlllo, I n ~ , Chlm, Act~, 256
(1997) 269; (c) F.A. Cotton, L.M. Daniels and C.A. Murillo, Inorg.
Chim. Acta, 224 (1994) 5.
[3] (a) W. Bragg and G.T. Morgan, Prec. R. Sac. London, Ser. A, 104
(1923) 437; (b) A. Tulinsky, C.R. Worthington and E. Pignataro,
Acta Crystallogr., i 2 ( 1959) 623; (c) A. Tulinsky, Acta Crystallogr.,
12 (1959) 634; (d) A. Tulinsky and C.R. Worthington, Acta
Crystallogr., 12 (1959) 626.
[4] (a) H. Koyama and Y. Suite, Bull. Chem. Sac. Jpn., 27 (1954) i 12;
(b) L. Hiltunen, M. Leskel& M. M~elii and L. NiinistqS,Acta Chem.
Scand., Ser. A, 41 (1987) 548.
[5] W. Clegg, D.R. Harbron, CD. Human, P.A. Hunt, I.R. Little and B.P.
Straughan, Inorg. Chim. Acta, 186 (1991) 51.
[6] A. Belforte, F. Calderazzo, U. Englert and J. Sw',ihle,lnorg. Chem., 30
( 1991 ) 3778.
[7] M. Corbett and B.F. Hoskins, lnorg. Nucl. Chem. Lett,, 6 (1970) 261.
[8] C.-F. Lee, K.-F. Chin, S.-M. Peng and C.-M. Che, J. Chem. Sac.,
Dalton Trans., (1993) 467.
[9] (a) K. Okamoto, Y. Watanab¢, T. Konno and J. Hidaka, Bull. Chem.
Sac. Jpn., 65 (1992) 3015; (b) T. Konno, T. N~ashio, K. Okamoto
and J. Hidaka, Inorg. Chem., 31 (1992) ! 160; (c) W. Cen, K.J. Hailer
and T.P. F,ehlner, Inorg. Chem., 30 (1991) 3120; (d) T. Karma, K.
Okamoto and J. Hidaka, lnorg. Chem., 33 (1994) 538.
[I01 AJ. Bum and G.W. Smith J. Chem. Sac., Chem. Commun., (1965)
394.
{!!1 P.G. Harrison, M J. Begley, T. Kikabhai and F. Killer J. Chem. Sac.,
Dalton Trans., (1986) 925,
{121 A.B. Blake, J. Chem. Sac., (1966) 569.
{13] S.-M. Peng and Y.-N. Lin, Acta Crystallogr.,Sect.C, 42 (1986) 1725.
[14] MK. Ehlert,S..I.Rettig,A. Start,R.C. Thompson and J.Trotter,Acta
Crystallogr.,Sect.C, 50 (1994) 1023.
[15] K. Okamoto, T. Konno and J. Hidaka, J. Chem. Sac., Dalton Trans.,
(1994) 533.
[16] G. Stucky and R.IL Rundle, J.An). Chem. Sac.,86 (1964) 4821.
1171 (a) R.L. H~low and S.H. Simonsen, Acta C~s|allogr., Sect. B, 33
( 1977 ) 2784; (b) J.T.Guy, .k.,.I.C.Cool~ f,R.D. Gilardi,J.L.Fllpl~no
Ander~on and C.F. Oe~,~o, Jr.,[p~¢8.Chem., 27 (1988) 635; (c) A.
BioTo,khy, G.og. Cal, G. l~,,vles,T.R. Gilbert, g.O. Onan and M.
Veidi~, J Am C'hev.t So,:., ,06 (1984) 4S96; (d) D.D~Swimk, D.O.
Niehon 'andRD, W;:;¢U, inorg. Chim, Acta, 7 (1973) 91; (e) RC
Dickinson, P T. Helm. W.A Baker, Jr., T.D. Black and W.li. Watson,
Jr.,inorg~Chem., 16 (1977) I~30; (f) M.R. Chu~¢hi!l,B~O. l~B~t
lindS J. MendS, lnor~ Cheni., 14 (197S) ~}¢~r',(g ) Jlap.B¢tllilitd,
Inor$, Chem,, O (It)O?) 49~; (h) R, B¢lford, D,E, Fenton and M,R,
Truter,L Chum. Sac., Dalton Traits,(1972) 2345: (|) NS. Gilland
M Stems, inofg, Ch~tn.,9 (1970) 1619; (j) J.A. Bertrand and J.A.
Kelley, [norg.Clmm., 8 (1969) 1982: (k) V..lodk, M. Korean, D.
Mak~ov~l, D. MilkoL A. Bro.~kovt~ov~l and G. Ondrcjovl0.,
Polyhedron, 15 (1996) 3129.
[181 (a) B. Beagley,C.A. McAulille,P.P.MaeRo~, P.T. Ndlfon lindR.G.
Prltchard,J. Cl~m. Sac., Cl~m. Commun., (1990) 309; (b) B.
Beasley, A.G. Mackte, P.P. Mate~r, C.A. McAuliffe, P.T. Ndifon and
R.G. PHtcMM, J.C'~m. Sac.,Dalton Ttans.,(1992) 1301.
|19] A.R. Sehak¢, .I.B.Vincent, Q. Li, P.D.W. Boyd, K. Foiling,J.C.
Huffman, D.N. Hendrlckson and (3.Chrlstou,Inorg.Chem., 28 (1989)
1915, and Refs. thedein.
[20l F.A. Colton, L.M Daniels, DJ. Maloney and C.A. Murillo, inorg.
Chtm, Acla, 252 (1996) 293, and Refs.thee|n.
[21 ] F.A. Cotton,J.H, Matontc and C.A. Mudllo. unpublished results.
[ 22] FA. Cotton. C.A. Murillo. X. Wang and H. Zhou unpublished results.
[23l RM. Rolmrls,J.Org. Cl~m., 14 (1949) 277.
|2~] A. Bino, F.A. Cotton and P. Fanwick, Inorg. Chem., 18 (1979) 3558.
[25] J.C. Bryan, F.A. Cotton, L.M Daniels, S.C. Haefner attd A.P.
S~Itelb~rger,Inorg.Chum., 34 (1995) 1875.
126] SHELXTL V$, Siemens lndustdal Automation. inc., Madison. WI.
1990.
|27] M. Steblexand H.B. Burg|, J. Am. Chem. Sac., 109 (1987) 1395.