The crystal and molecular structures of R 2 Sn(O 2 CR 1 )Cl: R = Me, t Bu and Ph; − O 2 CR 1 = o -(2-hydroxy-5-methylphenylazo)benzoate

The crystal and molecular structures of R2Sn(O2CR1)2: R = tBu, Ph; −O2CR1 = 2-[(E)-2-(2-hydroxy-5-methylphenyl)-diazenyl]benzoate

The crystal and molecular structures of two compounds of the general formula RiSn(O2CR1)2 are reported where R = tBu and Ph, and R1CO[unk] is the anion derived from 2-[(E)-2-(2-hydroxy-5-methylphenyl)-l-diazenyl]benzoic acid. For the R = tBu compound, the tin atom exists in a skew-trapezoidal bipyramidal geometry in which the trapezoidal plane is defined by two asymmetrically chelating carboxylate ligands and the organic residues lie over the weaker Sn–O interactions. A similar coordination geometry is found in the R = Ph compound which was isolated as a di-chloroform solvate. The chloroform molecules exert an influence on the molecular geometry in that a conformational change in the carboxylate ligand is induced in order to facilitate the formation of intermolecular hydrogen bonds. Systematic variations in the Sn-ligand parameters in these and related compounds are correlated with the varying Lewis acidity at the tin centers.