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Dissertation Information for Stephen M. Lynch

NAME:
- Stephen M. Lynch

DEGREE:
- Ph.D.

DISCIPLINE:
- Chemistry

SCHOOL:
- Emory University (USA) (2002)

ADVISORS:
- Albert Padwa

COMMITTEE MEMBERS:
- Frank E. McDonald
- Lanny S. Liebeskind

MPACT Status: Fully Complete

Title: The preparation and Diels-Alder cycloaddition chemistry of 2-amidofurans: Application toward the synthesis of indole alkaloids

Abstract: "Several methods for the synthesis of aza-substituted furans were investigated. These furans were found to undergo both bimolecular and intramolecular Diels-Alder cycloaddition with a wide variety of dienophiles to generate interesting azapolycyclic systems that offer the potential for natural product synthesis.

2-Carbamoyl furans were prepared by a Curtius rearrangement of the appropriately substituted furoyl azide in the presence of an alcoholic solvent. These amino-substituted furans were found to participate in bimolecular Diels-Alder cycloaddition at moderate temperatures to afford highly substituted oxabicylic products in good yield. Intramolecular cycloaddition with tethered ð-bonds afforded octahydroindolinones after a nitrogen assisted ring-opening and a subsequent 1,2-hydrogen shift. 2-Amidofurans were prepared by acylation of tert -butyl 2-furanyl carbamate with mixed anhydrides followed by the removal of the tert -butyl carbamate. The presence of an amido carbonyl group within the tether resulted in a substantial increase in the intramolecular Diels-Alder reactivity of these systems. Computational studies suggest that the facility of the intramolecular Diels-Alder cycloaddition of 2-amidofurans is dependent upon several favorable conformational features which are not present in furanyl systems devoid of carbonyl substitution.

As an extension of our studies dealing with the synthesis of biologically active natural products, the IMDAF methodology was applied toward the synthesis of several families of indole alkaloids. An approach to the aspidosperma alkaloid family was examined and which relied upon a key intramolecular [4+2]-cycloaddition of a 2-amidofuran across a tethered 2,3-indole ð-bond. A related intramolecular Diels-Alder reaction of a 2-carbamoyl furan across an indolyl acrylate was also used to generate the azepinoindole core skeleton characteristic of the iboga alkaloids."

MPACT Scores for Stephen M. Lynch

A = 0
C = 0
A+C = 0
T = 0
G = 0
W = 0
TD = 0
TA = 0
calculated 2008-04-07 07:42:11

Advisors and Advisees Graph