The current state-of-the-art synthesis for the formation of enantiomerically enriched all-carbon quaternary stereocenters in acyclic system relies on the formation of a single carbon-carbon bond per chemical step by asymmetric catalysis. These extraordinary sophisticated methods were logically classified among the most powerful and innovative ones. In this concept article, we are proposing a new retrosynthetic
Carbocupration/Zinc Carbenoid Homologation and β-Elimination Reactions for a New Synthesis of Allenes − Application to the Enantioselective Synthesis of Chiral Allenes by Deracemization of sp3-Organometallic Derivatives
作者:Jos P. Varghese、Irena Zouev、Lionel Aufauvre、Paul Knochel、Ilan Marek
straightforward carbocupration/zinc homologation/β-elimination reaction sequence allows the one-pot synthesis of polysubstituted allenes from acetylenic sulfoxides in excellent isolated chemical yields. Secondary zinccarbenoids were used for the homologation reaction, and so a new synthesis of 1,1-diiodoalkanes is described. This methodology also allows the synthesis of chiral allenes through thermodynamic
New Allene Synthesis via Carbocupration−Zinc Carbenoid Homologation and β-Elimination Sequence
作者:Jos P. Varghese、Paul Knochel、Ilan Marek
DOI:10.1021/ol006276t
日期:2000.9.1
the consecutive carbocupration-homologation-beta-elimination reactions on the easily accessible alkynyl sulfoxides or sulfones. This one-pot reaction also allows the preparation of functionalized allenes.