Cobalt(I)-Mediated [2 + 2 + 2] Cyclization of Allenediynes toward a Diastereoselective Approach to 11-Aryl Steroid Skeletons
作者:Marc Petit、Corinne Aubert、Max Malacria
DOI:10.1021/ol0485060
日期:2004.10.1
[reaction: see text] An 11-aryl steroid skeleton has been built in one step with a simultaneous introduction of the substituents at both C11 and C10 in 48% overall yield from a trans-allenediyne, whereas a formalAlderenereaction leading to a bicyclic yne-trienic compound becomes the major process from the cis-allenediyne.
Diastereoselective approach to 11-aryl steroid skeletons through a cobalt(I)-mediated [2+2+2] cyclization of allenediynes
作者:Marc Petit、Corinne Aubert、Max Malacria
DOI:10.1016/j.tet.2006.05.091
日期:2006.11
The cobalt(I)-mediated [2+2+2] cycloaddition reactions of allenediynes of yne-allene-yne type bearing an aryl group on the allene are described. The cyclizations are totally chemo- and regioselective and show low diastereoselectivities. η4-Complexed tricyclic (6,6,6) compounds were obtained in good yields as mixtures of endo/exo diastereomers. The cyclization is also compatible with an oxyfunctionality