One-Pot Enantioselective Formation of Eight-Membered Rings from Alkenyl Fischer Carbene Complexes and Ketone Enolates
作者:José Barluenga、Alejandro Diéguez、Félix Rodríguez、Josefa Flórez、Francisco J. Fañanás
DOI:10.1021/ja0264551
日期:2002.8.1
Eight-membered carbocycles with up to five new stereogenic centers are enantioselectively obtained following a one-pot procedure that involves the coupling of three components: an alkenylFischercarbenecomplex, a ketone enolate, and allyl lithium.
Tandem Enantioselective Conjugate Addition−Cyclopropanation. Application to Natural Products Synthesis
作者:Alexandre Alexakis、Sébastien March
DOI:10.1021/jo026262w
日期:2002.12.1
A tandem asymmetric conjugateaddition-cyclopropanation was developed, in which a cyclic or linear enone was converted to a TMS-protected 3-substituted-cyclopropanol in an efficient one-pot reaction. These compounds were then selectively cleaved to yield alpha-methyl-beta-alkyl ketones, alpha-methylene-enones, or chain extended gamma-alkyl-enones. This methodology was applied to the formal total synthesis