The development of new synthetic strategies and methodologies for complex alkaloid total synthesis : a concise synthesis of (+)-chimonanthine, (+)-WIN 64821, (-)-ditryptophenaline and related alkaloids

I. The Development of a General Strategy Towards Dimeric Hexahydropyrroloindole Alkaloids. A Concise Total Synthesis of (+)-Chimonanthine, (+)-Folicanthine and (-)Calycanthine. An efficient and convergent strategy for the synthesis of dimeric hexahydropyrroloindole alkaloids is described. The simultaneous formation of the vicinal quaternary stereocenters using a reductive dimerization reaction provides gram-scale access to an optically active key intermediate employed in the synthesis of (+)-chimonanthine, (+)-folicanthine, and (-)calycanthine. II. The Development of a General Strategy Towards Dimeric Hexahydropyrroloindole Alkaloids. A Concise Total Synthesis of (+)-WIN 64821, (-)-Ditryptophenaline and (-)-1'(2-Phenylethylene)-ditryptophenaline. The concise enantioselective total synthesis of (+)-WIN 64821 and (-)-ditryptophenaline in six and seven steps, respectively, from commercially available amino acid derivatives is described. The gram-scale synthesis of key intermediates and simultaneous introduction of the vicinal quaternary stereocenters provides a highly effective and preparative synthesis of these natural alkaloids. Additionally, the synthesis and structural confirmation of the natural alkaloid (-)-1 '-(2-phenylethylene)-ditryptophenaline is described. III. N-Heterocyclic Carbene-Alcohol Hydrogen Bonds. Studies and Application in the Amidation of Unactivated Esters. A single-step and catalytic amidation of unactivated esters with amino alcohols is described. Treatment of equimolar quantities of amino alcohols and unactivated esters with N,Nbismestiylimidazolylidene (5 mol%) affords the desired amides in high yield under mild reaction conditions.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Chemistry.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2008

Author dc:creator

• Schmidt, Michael Anthony, 1980-

Advisor dc:contributor.advisor

• Mohammad Movassaghi.

• Chemistry.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/43773

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/43773