Crystal structure of (1,4,7,10,13,16-hexa-oxa-cycloocta-decane-κ(6) O)potassium-μ-oxalato-tri-phenylstannate(IV), the first reported 18-crown-6-stabilized potassium salt of tri-phenyl-oxalatostannate.

The title complex, (1,4,7,10,13,16-hexa-oxa-cyclo-octa-decane-1κ(6) O)(μ-oxalato-1κ(2) O (1),O (2):2κ(2) O (1'),O (2'))triphenyl-2κ(3) C-potassium(I)tin(IV), [KSn(C(6)H(5))(3)(C(2)O(4))(C(12)H(24)O(6))] or K[18-Crown-6][(C(6)H(5))(3)SnO(4)C(2)], was synthesized. The complex consists of a potassium cation coordinated to the six oxygen atoms of a crown ether mol-ecule and the two oxygen atoms of the oxalatotri-phenyl-stannate anion. It crystallizes in the monoclinic crystal system within the space group P2(1). The tin atom is coordinated by one chelating oxalate ligand and three phenyl groups, forming a cis-trigonal-bipyramidal geometry around the tin atom. The cations and anions form ion pairs, linked through carbonyl coordination to the potassium atoms. The crystal structure features C-H⋯O hydrogen bonds between the oxygen atoms of the oxalate group and the hydrogen atoms of the phenyl groups, resulting in an infinite chain structure extending along a-axis direction. The primary inter-chain inter-actions are van der Waals forces.