Novel one-pot multi-bond forming reaction processes for the preparation of biologically active heterocycles

During the course of this PhD, a new one-pot thermal Overman rearrangement and ring-closing metathesis process was developed for the preparation of polycyclic compounds. In this method, commercially available phenols and anilines were converted to alkene derived allylic alcohols and then transformed...

Full description

Bibliographic Details
Main Author: Sharif, Salaheddin Ahmad Ibrahim
Published: University of Glasgow 2017
Subjects:
547
Online Access:http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.705616
Description
Summary:During the course of this PhD, a new one-pot thermal Overman rearrangement and ring-closing metathesis process was developed for the preparation of polycyclic compounds. In this method, commercially available phenols and anilines were converted to alkene derived allylic alcohols and then transformed via a one-pot process into 5-amino 2,5-dihydro-1-benzoxepines and 5-amino 2,5-dihydro-1H-benzazepines. The synthetic utility of these compounds was explored with the preparation of highly substituted hydroxylated analogues as well as a highly active hypotensive agent. A novel one-pot process was also developed for the synthesis of allylic amide derived 2H-chromenes. The key substrates, propargyloxy cinnamyl alcohols were rapidly prepared from readily available salicylaldehydes. One-pot thermal Overman rearrangement of the corresponding allylic trichloroacetimidates, followed by a gold(I)-catalysed hydroarylation gave the 2H-chromenes in high yields. A mild chemoselective method for the oxidation of the 2H-chromenes to give coumarins was also discovered.