New efficient construction of the ABC core of the taxoids via a sequence of consecutive cobalt(I)-mediated [2 + 2 + 2] and [4 + 2] cyclizations.
[reaction: see text] A new and efficient sequence of two consecutive cyclizations, a cobalt(I)-mediated [2 + 2 + 2] cyclotrimerization and a Diels-Alder reaction, is proposed to allow the formation of the ABC core of the taxoids in 65% overall yield, starting from an acyclic polyunsaturated precursor.
Petit
Marc
M
Université Pierre et Marie Curie (Paris 6), Laboratoire de Chimie Organique de Synthèse associé au CNRS, Tour 44-54, 2ème étage, Case 229, 4 place Jussieu 75252, Paris Cedex 05, France.
Chouraqui
Gaëlle
G
Phansavath
Phannarath
P
Aubert
Corinne
C
Malacria
Max
M