Triorganotin carboxylates – synthesis and crystal structure of 2-methyl-1H-imidazol-3-ium catena-O,O′-oxalatotriphenylstannate

Abstract

The reaction of bis(2-methyl-1H-imidazol-3-ium) oxalate, [C4H7N2]2[C2O4], and bis(triphenyltin) oxalate, [(Ph3Sn)2(C2O4)], in methanol at room temperature yielded the formation of 2-methyl-1H-imidazol-3-ium catena-O,O′-oxalatotriphenylstannate, [C4H7N2][Ph3Sn(C2O4)] (1), which crystallizes in the monoclinic space group P21/c with Z=8, a=16.9334(14) Å, b=17.3251(14) Å, c=14.5114(10) Å, β=90.590(2)°, and V=4257.0(6) Å3. The oxalate ligand of 1 displays a bridging coordination mode and thus links two SnPh3 moieties through an axial coordination leading to the propagation of infinite polymeric chains along the c axis. All Sn(IV) atoms exhibit a trigonal bipyramid geometry. The negative charge of [Ph3Sn(C2O4)]- moieties is compensated by the presence of surrounding noncoordinating 2-methyl-1H-imidazol-3-ium cations. From a supramolecular point of view, the Sn-based chains are connected to one another through N-H···O hydrogen bond interactions involving oxalate ligands of distinct strands and doubly by the [C4H7N2]+ cations. The topology of the resulting crystal packing can be described as a two-dimensional layer network.

Keywords

• organotin (iv) carboxylates
• oxalate ligand
• self-assembly
• triphenyltin
• x-ray crystallography