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Cyclization cascade of allenyl azides: a dual mechanism.

ABSTRACT: A density functional theory based computational approach to describing the mechanistic course of the allene azide cycloaddition cascade sequence has been developed. The results of these calculations permit characterization of key reactive intermediates (diradicals and/or indolidenes) and explain the different behaviors observed in the experimental studies between conjugated and nonconjugated species. Furthermore, computational analysis of certain intermediates offer insight into issues of regioselectivity and stereoselectivity in cases where different reaction channels are in competition, suggesting suitable substitutions to achieve a single regioisomer in the indole synthesis via azide-allene cyclization.

SUBMITTER: Lopez CS

PROVIDER: S-EPMC2527537 | biostudies-literature | 2007 Jun

REPOSITORIES: biostudies-literature

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Cyclization cascade of allenyl azides: a dual mechanism.

López Carlos Silva CS Faza Olalla Nieto ON Feldman Ken S KS Iyer Malliga R MR Ii D Keith Hester DK

Journal of the American Chemical Society 20070527 24

A density functional theory based computational approach to describing the mechanistic course of the allene azide cycloaddition cascade sequence has been developed. The results of these calculations permit characterization of key reactive intermediates (diradicals and/or indolidenes) and explain the different behaviors observed in the experimental studies between conjugated and nonconjugated species. Furthermore, computational analysis of certain intermediates offer insight into issues of regios ...[more]

PMID: 17530848

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