Preparation of 2-silicon-substituted 1,3-dienes and their Diels-Alder/cross-coupling reactions

J Org Chem. 2009 Nov 6;74(21):8290-7. doi: 10.1021/jo901919m.

Abstract

2-Triethoxysilyl-substituted 1,3-butadiene has been prepared in 30-g quantities from chloroprene via a simple synthetic procedure. Silatrane- and catechol-substituted analogues of this main group element substituted diene were then prepared on a 10-g scale by ligand exchange and characterized by X-ray crystallography in addition to standard spectroscopic techniques. 2-Dimethylphenylsilyl-1,3-butadiene has also been prepared from chloroprene on an 8-g scale. Diels-Alder reactions of these dienes are reported as well as subsequent TBAF-assisted/Pd-catalyzed Hiyama cross-coupling reactions of those Diels-Alder adducts. Silicon-substituted cycloadducts and cross-coupled products were also characterized by NMR spectroscopy and, in two cases, by X-ray crystallography.