Cascade Metathesis Reactions for the Synthesis of Taxane and Isotaxane Derivatives

Cong Ma (1) , Aurélien Letort (2) , Rémi Aouzal (1) , Antonia Wilkes (2) , Gourhari Maiti (1) , Louis J. Farrugia (2) , Louis Ricard (3) , Joëlle Prunet (2)

1 DCSO - Laboratoire de synthèse organique
2 WestCHEM
3 LCM - Laboratoire de chimie moléculaire

Tricyclic isotaxane and taxane derivatives have been synthesized by a very efficient cascade ring-closing dienyne metathesis (RCDEYM) reaction, which formed the A and B rings in one operation. When the alkyne is present at C13 (with no neighboring gem-dimethyl group), the RCEDYM reaction leads to 14,15-isotaxanes 16a,b and 18b with the gem-dimethyl group on the A ring. If the alkyne is at the C11 position (and thus flanked by a gem-dimethyl group), RCEDYM reaction only proceeds in the presence of a trisubstituted olefin at C13, which disfavors the competing diene ring-closing metathesis reaction, to give the tricyclic core of Taxol 44.

Domains: Chemical Sciences; Organic chemistry

Cong Ma, Aurélien Letort, Rémi Aouzal, Antonia Wilkes, Gourhari Maiti, et al.. Cascade Metathesis Reactions for the Synthesis of Taxane and Isotaxane Derivatives. Chemistry - A European Journal, 2016, 22 (20), pp.6891-6898. ⟨10.1002/chem.201600592⟩. ⟨hal-01355946⟩