This article was downloaded by: [German National Licence 2007]
On: 21 September 2010
Access details: Access Details: [subscription number 777306419]
Publisher Taylor & Francis
Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 3741 Mortimer Street, London W1T 3JH, UK
Phosphorus, Sulfur, and Silicon and the Related Elements
Publication details, including instructions for authors and subscription information:
http://www.informaworld.com/smpp/title~content=t713618290
Inorganic Heterocycles Containing Two or Three Transition Metal Atoms
Herbert Plenioa; Michael Witta; Frank T. Edelmanna; Thomas Henkela; Mathias Noltemeyera; Frank
Pauera; Dietmar Stalkea; George M. Sheldricka; Herbert W. Roeskya
a
Institut für Anorganische Chemie der Universität Göttingen, Göttingen, F.R.G.
To cite this Article Plenio, Herbert , Witt, Michael , Edelmann, Frank T. , Henkel, Thomas , Noltemeyer, Mathias , Pauer,
Frank , Stalke, Dietmar , Sheldrick, George M. and Roesky, Herbert W.(1989) 'Inorganic Heterocycles Containing Two or
Three Transition Metal Atoms', Phosphorus, Sulfur, and Silicon and the Related Elements, 41: 3, 335 — 339
To link to this Article: DOI: 10.1080/10426508908039722
URL: http://dx.doi.org/10.1080/10426508908039722
PLEASE SCROLL DOWN FOR ARTICLE
Full terms and conditions of use: http://www.informaworld.com/terms-and-conditions-of-access.pdf
This article may be used for research, teaching and private study purposes. Any substantial or
systematic reproduction, re-distribution, re-selling, loan or sub-licensing, systematic supply or
distribution in any form to anyone is expressly forbidden.
The publisher does not give any warranty express or implied or make any representation that the contents
will be complete or accurate or up to date. The accuracy of any instructions, formulae and drug doses
should be independently verified with primary sources. The publisher shall not be liable for any loss,
actions, claims, proceedings, demand or costs or damages whatsoever or howsoever caused arising directly
or indirectly in connection with or arising out of the use of this material.
0 1989 Gordon
Phosphorus, Suuur and Silica. Vol. 41, pp. 335-339
Reprints available directly from the publisher
Photocopying permitted by license only
and Breach, Science Publishers, Inc.
Printed in the United Kingdom
Downloaded By: [German National Licence 2007] At: 06:20 21 September 2010
INORGANIC HETEROCYCLES CONTAINING TWO OR THREE
TRANSITION METAL ATOMS
HERBERT PLENIO, MICHAEL WITT, FRANK T.EDELMANN,
THOMAS HENKEL, MATHIAS NOLTEMEYER, FRANK P A U E R ,
DIETMAR STALKE, GEORGE M. SHELDRICK AND
HERBERT w. ROESKY*
Institut fiir Anorganische Chemie der Universitat
Gijttingen, Tammannstr. 4, D-3400 Gijttingen, F.R.G.
Abstract
Syntheses and structures o f novel
inorganic heterocycles containing two or three
transition metal atoms are reported. Examples
include the first triazatrimetallabenzene
derivative, [Cp*Ta(Cl)N] 3 , as well as eightmembered phosphazene rings containing two vanadium
atoms.
INTRODUCTION
The chemistry o f unsaturated inorganic heterocyles is
of
current interest. Recently we have developed general
.
synthetic routes to c y c l o m e t a l l a p h o s p h a z e n e s 1 - 3 Typical
examples are the six-membered heterocycles 1
- and -2 , in
which a phosphorus atom o f the phosphazene ring is replaced by a transition metal atom:
H
..
Xn
Xn
335
PS - D
336
H.W.ROESKY et al.
RESULTS AND DISCUSSION
Four-membered titanaheterocycles are formed in the re-
- with
action of the silylated amino-iminophosphorane 2
4
Two cyclic products, orange yellow 4- and pale
TiC14
.
Downloaded By: [German National Licence 2007] At: 06:20 21 September 2010
yellow 5.
- are isolated in moderate yield by fractional
crystallization from acetonitrile:
/N
S iMe
Ph P‘N(SiMe3l2
+ TiC14
-
SiMe3
(CH3CN)C1 Ti/N\
\N/
4
-
PPh2
SiMe3
+
S iMe
I
/N\C1
Ph2P\
/
Ti fCH3CN)
\N
N\ / \
(CH3CN)Ti
C$/pph2
N
-5
I
SiMe
3
The molecular structures of 4- and -5 were determined by
X-ray crystallography.
Nitrido complexes of the early transition metals
form a variety o f different structures5. Monomers and
dimers are known as well a s tri- and tetranuclear complexes and linear polymers. We describe here the preparation of the first cyclic trimer of a metal nitride.
Cp*TaC14 reacts with N(SnMe3)3
room temperature
6 7 % yield:6
t o
in toluene solution at
give the yellow metallacycle 6 in
HETEROCYCLES
CONTAINING TRANSITION METALS
337
This very stable compound can be sublimed at ca. 25OoC
under high vacuum. The mass spectrum shows the molecular ion and the IH-NMR data (singlets at
6
2.09 and
2.13 ppm) indicate that the molecule contains non-
*
equivalent Cp ligands. An X-ray structure determination clearly shows the presence of the first triaza-
Downloaded By: [German National Licence 2007] At: 06:20 21 September 2010
tritantalabenzene derivative:
The six-membered T a N ring is not exactly planar but
3 3
slightly distorted towards a boat conformation. The
average tantalum-nitrogen bond length i s 188(2)
pm.
This value lies right between those found for Ta=NR
(174-178
pm) and Ta-NR2 (195-203 pm).
It is interest-
ing to note that a cyclic trimer of a metal nitrido
complex had already been postulated by Hoffmann et al.
in 1 9 8 6 7
.
Two eight-membered ring systems have recently been
discovered using different synthetic routes. Treatment o f CpCp*ZrCl
with Me SnNSNSnMe gives a n un2
3
3
saturated eight-membered metallacycle 1 with two
8
zirconium atoms in the ring :
2CpCp*ZrCI2 + 2 Me,SnNSNSnMe,
-
- 4 Me,SnCl
/
NSN
,
CpCp*Zr
zrcpcp*
'NSN
/
338
H.W.ROESKY
et al.
The yellow complex 1
- is isolated in 6 5 % yield and the
by-product Me SnCl is easily removed by sublimation.
3
The corresponding hafnium derivative - is obtained in
an analogous manner. IH-NMR spectra of 1
- and - exhibit
two sets of signals for the Cp and Cp’ligands in a
ratio of approximately 1 : 2 .
This can be explained by
the existence of two isomers. It can be assumed that
Downloaded By: [German National Licence 2007] At: 06:20 21 September 2010
isomer B is favored for steric reasons:
CPt
Zr -( NSN l2
CP /
- Zr
/
CP*
cp\
Zr
\
CP
- ( NSN
)2-
/
CP*
\
CP
Zr
cp*/
B
A
Silylated iminophosphoranes were used as starting
materials for the synthesis of the first eight-membered cyclometallaphosphazene ring system 9 ’ 1 0 , Treatment of VOCl
in aceto3
nitrile solution results in the formation of dark red,
crystalline
3
2-
with Ph2P[N(SiMe3)2]NSiMe
in 80% yield. This material is formed
by elimination of four equivalents of M e Sic1 and
3
migration of trimethylsilyl groups to the oxygen
atoms:
Ph
N SiMeJ
\ /
2
P
Ph’
‘N(SiMe,),
?
Me3SiOV-N =PPh,
+ 2V0CI3
-
I
II
NI
‘+
P
h
N
It
‘N-VOSiMe3
I
--9
+ 4 MejSiCl
CI
An X-ray analysis demonstrates that the ring system is
exactly planar. The two vanadium atoms are tetrahedrally coordinated. The V-N distances (ave. 1 6 7 . 0 ( 5 ) )
are similar to those found in vanadium nitrene complexes. Using Ph2P(NSiMe 3 )C1 and Me3SiNVC13 as
starting materials the tetrachloro derivative of the
new ring system was synthesized in high yield:
HETEROCYCLES CONTAINING TRANSITION METALS
339
Downloaded By: [German National Licence 2007] At: 06:20 21 September 2010
ACKNOWLEDGEMENTS
The authors thank the Deutsche Forschungsgemeinschaft,
the Fonds der Chemischen Industrie and the VolkswagenStiftung for their generous support of this work.
REFERENCES
1.
H. w. Roesky, K. V. Katti, U. Seseke, M. w i t t y
E. Egert, R. Herbst and G. M. Sheldrick, Angew.
Chem. 9 8 , 4 4 7 ( 1 9 8 6 ) , Angew. Chem. Int. Ed. Engl.
25,
2.
3.
4.
5.
6.
7.
8.
9.
10.
477(1986).
H. W. Roesky, K. V. Katti, U. Seseke, H. G.
Schmidt, E. Egert, R. Herbst and G . M. Sheldrick,
J. Chem. SOC. Dalton Trans. 1 9 8 7 , 8 4 7 .
K. V. Katti, H. W. Roesky and M. Rietzel, Inorg.
Chem.
- -2 6 , 8 1 4 ( 1 9 8 7 ) .
M. Witt, H. W. Roesky, D. Stalke, F. Pauer,
T. Henkel and G . M. Sheldrick, J. Chem. SOC.
Dalton Trans., in press.
K. Dehnicke and J. Strahle, Angew. Chem. 9 3 , 4 5 1
( 1 9 8 1 ) , Angew. Chem. Int. Ed. Engl. 2 0 , 4 1 3 ( 1 9 8 1 ) .
H. Plenio, H. W. Roesky, M. N o l t e m e y z and G. M.
Sheldrick, Angew. Chem., in press.
R. A. Wheeler, R. Hoffmann and J. Strahle, J. Am.
Chem. SOC. 1 0 8 , 5 3 8 1 ( 1 9 8 6 ) .
H. Plenio and H. W. Roesky, 2 . Naturforsch., in
press.
M. Witt, H. W. Roesky, M. Noltemeyer and G. M.
Sheldrick, Angew. Chem. 100, 8 5 2 ( 1 9 8 8 ) , Angew.
Chem. Int. Ed. Engl. 2 7 , 8 5 0 ( 1 9 8 8 ) .
M. Witt and H. W. Roesky, unpublished results.