Synthesis and spectroscopic studies of thienyl triorganotin(IV) compounds. Crystal structures of [2-(4,4-dimethyl-2-oxazolinyl)-3-thienyl]dimethyltin N, N-dimethyldithiocarbamate and [2-(4,4-dimethyl-2-oxazolinyl)-3-thienyl]diphenyltin chloride

Abstract

Two series of stannylated thiophenes of formula ( Z-C 4H 2SnR 2X ( Z = 3-(2-pyridyl) and 2-(4,4-dimethyl-2-oxazolinyl); R = Me, nBu, Ph, p-tolyl and cHex; X = Cl, Br, I, OH, SC(S)NMe 2, and 8-quinolinolyl) have been prepared and their structures established by 119 m Sn Mössbauer and NMR ( 13C and 119Sn) spectral analyses. A pronounced C, N-chelate bonding mode is inferred for the 3-(2-pyridyl)-2-thienyl ligand in the first series, the tin atoms thus being essentially five-coordinate with trans-C 3SnNX trigonal bipyramidal geometries. Crystal structure determinations on two products in the second series, namely [2-(4,4-dimethyl-2-oxazolinyl)-3-thienyl]dimethyltin N, N-dimethyldithiocarbamate ( 1) and [2-(4, 4-dimethyl-2-oxazolinyl)-3-thienyl]diphenyltin chloride ( 2), confirmed the spectroscopic indications of pentacoordinate trigonal bipyramidal tin environments and revealed that the oxazolinyl nitrogen is the intramolecularly coordinated donor atom in each case and is located in an apical position with respect to the C 3Sn trigonal girdle; the Sn-N bond length in 2 (2.580(8); 2.525(7) Å) is relatively shorter than in 1 (2.720(3) Å). The apical angle for 1 (162.12(7)°) shows the molecule to be more distorted than 2 (168.4(2) and 169.9(2)°).