The synthesis of the tricyclicABC ring-system of Taxol® (paclitaxel) is described. This direct route involves sequential reactions employing the carbometallation of a propargy] alcohol, followed by a cis-alkene tether controlled stereoselective intramolecular Diets-Alder reaction to generate the AB-ring system and ring closing metathesis (RCM) of the pendant allyl substituents to construct the C ring
Part 2: Efficient strategies for the construction of variably substituted bicyclo[5.3.1]undecenones (AB-taxane ring systems) and their conversion to tricyclo[9.3.1.0<sup>3,8</sup>]pentadecenones (ABC taxane ring systems) and bicyclo[2.2.2]octanones
作者:Nidia P Villalva-Servín、Alain Laurent、Alex G Fallis
DOI:10.1139/v03-201
日期:2004.2.1
ring-closing metathesis (RCM) afforded the ABC taxane corestructure. Enone accelerated [3,3] sigmatropic rearrangements (Cope rearrangements) generated the bicyclo[2.2.2]octanone nucleus. In the presence of a Lewis acid, the dienophile precursor underwent a tandem reaction via the adduct directly to the bicyclo[2.2.2]octanones. This is the first example of a novel enone accelerated carbocycle Cope rearrangement