Regioselective Synthesis of Enones via a Titanium-Promoted Coupling of Unsymmetrical Alkynes with Weinreb Amides
作者:Sajan Silwal、Ronald J. Rahaim
DOI:10.1021/jo5014417
日期:2014.9.5
A modular titanium-promoted coupling of unsymmetrical internal alkynes with Weinreb amides is described. The coupling reaction takes place at room temperature and affords E-trisubstituted enones in moderate to good yields with high levels of regioselectivity. The system shows moderate chemoselectivity.
Stereoselective Syntheses of Trisubstituted Olefins via Platinum Catalysis: α-Silylenones with Geometrical Complementarity
作者:Douglas A. Rooke、Eric M. Ferreira
DOI:10.1021/ja1058197
日期:2010.9.1
The stereoselective syntheses of alpha-silylenones using catalytic PtCl(2) are reported. Via alkyne activation, alpha-hydroxypropargylsilanes are converted to (Z)-silylenones through a highly selective silicon migration. The complementary (E)-silylenones are accessed by a regioselective hydrosilylation of the ynone precursor. The synthetic utility of these compounds is demonstrated in cross-coupling