STUDIES TOWARD THE SYNTHESIS OF TMC-95A AND DEVELOPMENT OF AN ENANTIOSELECTIVE PUMMERER REACTION FOR THE SYNTHESIS OF 3,3-SPIROCYCLIC OXINDOLES
Open Access
Author:
Karatjas, Andrew George
Graduate Program:
Chemistry
Degree:
Doctor of Philosophy
Document Type:
Dissertation
Date of Defense:
May 30, 2006
Committee Members:
Ken S Feldman, Committee Chair/Co-Chair Blake Peterson, Committee Member RAYMOND LEE FUNK, Committee Member James Patrick Runt, Committee Member
Keywords:
Pummerer TMC-95
Abstract:
Oxidative cyclizations of tryptophan derivatives have seen little use in total synthesis. The use of this methodology in a model system of TMC-95A was explored. This method failed to lead to products for continuation of the synthesis. A new approach to indole C(3) cyclizations was proposed using Pummerer reaction chemistry. This method was found to be successful on both simpler tryptophan derivatives and on the TMC-95A model system, leading to the correct regiochemistry and stereochemistry for TMC-95A.
Further extension of the Pummerer reaction methodology was desired through attempts toward an enantioselective variant with carbon nucleophiles. Results with silyl enol ether nucleophiles showed excellent stereoselectivity.
