An Expeditious Route to Both Enantiomers of All Carbon Quaternary Stereocenters at C-3 Carbon of Lactams via [3,3]-Sigmatropic Rearrangement: Total Synthesis of (−)-Physostigmine
作者:Ganesh Pandey、Jagadish Khamrai、Akash Mishra
DOI:10.1021/ol503766y
日期:2015.2.20
A diastereoselective route to all carbonquaternary stereocenters at the C-3 position of cyclic lactams has been developed via Johnson–Claisen rearrangement of γ-hydroxy-α, β-unsaturated lactams. It has been observed that olefin geometry plays an important role in the development of the absolute stereochemistry of the product. The dependence of the product configuration on the olefin geometry is explained
Generation of All-Carbon Quaternary Stereocenters at the C-3 Carbon of Lactams via [3,3]-Sigmatropic Rearrangement and Revision of Absolute Configuration: Total Synthesis of (−)-Physostigmine
作者:Ganesh Pandey、Jagadish Khamrai、Akash Mishra
DOI:10.1021/acs.orglett.7b03537
日期:2018.1.5
via Johnson–Claisen rearrangement of γ-hydroxy-α,β-unsaturated lactams. It has been observed that olefin geometry plays an important role in the development of the absolute stereochemistry of the product. Dependence of product configuration on the olefin geometry is explained by postulating probable transition states. The success of this method has been shown for multigram-scale synthesis of these substituted