Synthesis, characterization, and crystal structures of tin(IV) 1-pyrrolethiocarboxylates

Abstract

Tin 1-pyrrolecarbothioates (1-pyrrolethiocarboxylates) SnR4–nLn(L = OSC[graphic omitted]H, n= 1–4) have been synthesized and characterized by i.r., n.m.r. (1H, 13C, and 119Sn), and 119Sn Mossbauer spectral studies. X-Ray crystal and molecular structure analyses were performed on the compounds SnPh3L, SnMe2L2, SnPhL3, and SnL4. The triphenyltin complex is tetrahedral with a sulphur-bonded ligand. The bis complex can be considered to be essentially tetrahedral or as highly distorted octahedral if very weak Sn–O interactions (average bond length 2.65 A) are taken into account. The phenyltin tris complex contains a seven-co-ordinated tin atom in a distorted pentagonal-bipyramidal environment with all the three ligands bound to the tin in an anisobidentate fashion (average Sn–O 2.506 A). The complex SnL4 shows a distorted-octahedral co-ordination geometry with two thiocarbamates functioning as bidentate chelates, the other two as monodentate ligands through the sulphur atom. In solution, these structures are essentially retained, as indicated by the n.m.r. spectral features.