Cation intercalation in layered anionic frameworks, Cationic
ligands and assembling of complex ions
We have been interested in in layered structures of dipicolinate complexes constructed by
π-π interactions and also to generalize the interlayer separation while encapsulating
organo-cations. A series of study carried out whose slides are listed below:
O
O
stacking interactions
O
O
O
O
O
O
N
M
N
O
O
O
O
O
O
O
N
M
N
O
O
O
O
O
N
M
N
O
O
O
O
π-π stacking generally observed in bis-dipicolinates
Background: We have carried out extensive work on layered structures from anion assemblies of metal dipicolinates to encapsulate
organocations
[enH2][NiL2].3H2O
[penH2][CuL2].5H2O
[enH2][M(en)2(H2O)2].[CuL2]2.H2O
[bamH]2[NiL2].5H2O
[docH2][CuL2].2H2O
Packing diagram of the complexes showing the [ML2]2- (ball and stick mode) as inorganic layer and amines (space filled mode) as
organic layer. En = ethylenediamine, pen =1,5-pentanediamime , bam = 4-aminobenzylamine, doc = 1,8-diaminodecane
Inorg. Chim. Acta 363 (2010) 1479; Inorg. Chem. Commun. 13 (2010) 350
Packing diagram of dipicolnate complexes with alkali metal ions:
{[Na(H2O)2]2[CuL2].2H2O}n
{[K2(H2O)7][CuL2]}n
{Ca(H2O)4][CuL2].2H2O}n
[Mg(H2O)5][CuL2].2H2O
Inorg. Chim. Acta 363 (2010) 1479
Packing diagram showing intercalation of histidinium and ornithinium cations: (A-B-A manner)
[L-hisH2][CuL2].5H2O
[L-orniH2][CoL2].9H2O
Inter-layer separation generated by amines and amino acid dications :
Complex
Cation of
Inter-layer separation (Å)
[enH2][NiL2].3H2O
ethylenediamine
8.2
[pnH2][CuL2].xH2O*
1,3-propanediamine
10.4
[penH2][CuL2]. 5H2O
1,5-diaminopentane
11.2
[L-orniH2][CoL2].9H2O
L-ornithine
11.5
[L-hisH2][CuL2].5H2O
L-histidine
11.8
[bamH]2[CuL2].5H2O
4-amino benzyl amine
14.3
Polyhedron 30 (2011) 22
Mn(II) / Cu(II) dipicolinate with adeninium cations and their supramolecular architectures:
ORTEP diagram of [1H, 9H-ade][3H,7Hade][CuL2].3H2O
Adeninium ribbon in layers of complex anion
Close view of 1D zigzag adeninium ribbon with H-bond distances
Cryst. Growth Des. 10 (2010) 3242
Mn(II)-dipicolinate with cytosinium cations and its supramolecular architectures:
ORTEP diagram of [1H, 3H-cyt]2
[MnL2(H2O)].2cyt.6H2O
Packing diagram of [1H, 3H-cyt]2 [MnL2(H2O)].2cyt.6H2O
viewed along a axis
Close view of tetrameric hydrogen bonded assembly of cytosine
Cryst. Growth Des. 10 (2010) 3242
Stabilization of protonated adenine and cytosine cations in polymeric Mn(II) / Cu(II)-quinolinate complex and in flexible polycarboxylic systems:
Adeninium cations in layers of
{[1H, 9H-ade]2[MnL2].4H2O}n
Discrete cytosine-cytosinium assembly in
layers of adipic acid
Cytosinium cations in layers of
{[1H,3H-cyt]2[CuL2]∙6H2O}n
Trimeric cytosine-cytosinium assembly in
layers of citric acid
Inorg. Chem. Commun. 13 (2010) 1244;
J. Mol. Struct. 1001 (2011) 134
(a)
(c)
(b)
In the present study we have determined structures of few nickel
complexes and demonstrate the stacking of (a) (HQ)2[NiL2].5H2O, (b)
(H5AQ)2[NiL2].4H2O, (c) (H8HQ)2[NiL2].6H2O, (d) H2[NiL2].4H2O.
([NiL2]2- in ball and stick mode, in a-c cations are in space filled mode).
Where Q = quinoline, 8HQ = 8-hydroxyquinoline, 5AQ = 5aminoquinoline. This happens as the quinolines have greater tendency
for π-stacking interactions.
We also establish the solid state cation exchange reactions shown below:
(d)
H2[NiL2].3H2O (4)
Quinoline
Solid State
(HQ)2[NiL2].5H2O (1)
5-aminoquinoline
Solid State
(Washed with MeOH)
(H5AQ)2[NiL2].4H2O (2)
M(OAc)2 + LH2
+ Cat
MeOH
[(CatH)(ML2)]n (nH2O)m + AcOH
O
When
O
M = Mn(II)
M = Cu(II)
Cat = adenine
Cat = cytosine
m=4
m=6
1
2
O
N
L
O
Coordination of cationic sodium cluster [Na4(μ-H2O)6(H2O)10]4+
Cationic sodium cluster
[Na4(μ-H2O)6(H2O)10]4+
Coordination by cationic ligands
[Mg(H2O)5] units are coordinated
to dipicolnate complex
[CuL2] dianions are held I by
polymeric aqua-bridged sodium
cations
[CuL2] dianions are hel by polymeric
aqua-bridged potassium cations
[Ca(H2O)4] 2+ units are bridged
by the dipicolinate complex
anions
Assembling as well as Scrambling:
Multiple cobalt containing cations and anions
Combination of copper and cobalt complex ions