Synthesis and characterization of new di-n-butyl [bis{dimethyl-2-(3-oxo-5-phenyl(4-subtituted)-penten-5-ato)malonatesl]tin(IV): The crystal structure of di-n-butyl[bls{dimethyl-2-[5-(4-nitrophenyl)-3-oxo-penten-5-ato]malonate}]tin(IV)

摘要

The synthesis of four new di-n-butyl[bis{dimethyl-2-(3-oxo-5-phenyl(4-subtituted)penten-5-ato)malonates}]tin(IV) 2a-2d is reported. These complexes have been characterized by H-1, C-13, Sn-119 NMR, HMQC, HMBC, infrared spectroscopy and mass spectrometry (FAB). Their structures in CDCl3 Solution show a distorted octahedral geometry with a trans disposition of the n-butyl substituents. The Sn-119 NMR study at low variable-temperature indicates the presence of trans anti- and syn-isomers, and solid-state C-13 and Sn-119 NMR spectra of compound 2d give also evidence of the mixture of trans isomers. The X-ray diffraction study of compound 2d at 168 K shows only the trans syn-isomer, where the metal is six-coordinated in a skewed trapezoidal bipyramidal (STB) geometry. (c) 2005 Elsevier Ltd. All rights reserved.