Total synthesis of (+)-ent-vetiverianine a via Lewis acid-mediated cyclization

Abstract

Herein, we describe the first total synthesis of (+)-ent-vetiverianine A, which exhibits a 5/6/6-fused tricyclic structure. The key reactions, including Lewis acid-mediated cyclization, Mukaiyama hydration, enantioselective Shi epoxidation, Birch reduction,...

Selective preparative ‘oxidase phase’ in sesquiterpenoids: the radical approach

“…The first synthesis of the enantiomer of the natural product ( ent - 141 ) to be reported was by Sugita's group in 2022, which made use of the inexpensive 3-methoxytoluene ( 132 ) as the starting material (Scheme 14). 41 Birch reduction and acetalization led to trisubstituted alkene 133 and from there to enantioenriched cyclohexenone 134 , employing a Shi asymmetric epoxidation and acidic treatment of the resulting epoxide. Steric interactions drove the subsequent conjugated addition of γ-butenyl Grignard reagent stereoselectively from the α-face of the protected enone giving ketone 136 .…”