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 P 2 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.