Ueber Tetraaryl-Methan-Analoga in der Gruppe 14.III. Ar4Sn/Pb (Ar=Ph, p-, m-, o-Tol, 2,4-Xyl und 2,5-Xyl): Gegenueberstellung von Bindungslaengen und Winkeln, von NMR chemischen Verschiebungen und Kopplungskonstanten und von Schwingungsdaten

Article abstract of DOI:10.1016/0022-328X(94)80074-X

The title compounds have been synthesized Grignard reactions or pyrolysis of diplumbanes respectively.The crystal structures of m-Tol4Pb and Ph4Pb (redetermination) have been determined.All eight compounds (Ph/Tol)4(Sn/Pb) are S₄ symmetric and contracted along this unique axis.The 13C-NMR chemical shifts and the couplings 1J(119Sn/207Pb-13C) as well depend additively upon the methyl substituents.The ratios 1K(207Pb-13C):1K(119Sn-13C) of the reduced coupling constants are all near to 1.61; a comparison with values from the literature for alkyl, alkenyl and alkinyl substituents is given.The ratio δ(207Pb):δ(119Sn) results in 2.28.IR (700 down to 200 cm^-1) and Raman (700 down to 50 cm^-1) data are given.Key words: Tin; Lead; Group 14; Vibrational data; Nuclear magnetic resonance; Crystal structure