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Free radical-mediated aryl amination: convergent two- and three-component couplings to chiral 2,3-disubstituted indolines.

ABSTRACT: 5-exo-trig Cyclization of an aryl radical to the nitrogen of an azomethine is used as the key annulating step in a modular preparation of 2,3-cis- and trans-disubstituted indolines. The precursors are readily prepared by phase-transfer-catalyzed Michael addition of a glycine Schiff base to a variety of acceptors. When the more reactive alkylidene malonate Michael acceptors are implemented, a one-pot three-component coupling is possible. The net result is a convergent [3 + 2] coupling strategy for the construction of highly functionalized indolines, a substructure occurring in numerous biologically active natural products.

SUBMITTER: Viswanathan R

PROVIDER: S-EPMC9129149 | biostudies-literature | 2008 Apr

REPOSITORIES: biostudies-literature

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Free radical-mediated aryl amination: convergent two- and three-component couplings to chiral 2,3-disubstituted indolines.

Viswanathan Rajesh R Smith Colin R CR Prabhakaran Erode N EN Johnston Jeffrey N JN

The Journal of organic chemistry 20080320 8

5-exo-trig Cyclization of an aryl radical to the nitrogen of an azomethine is used as the key annulating step in a modular preparation of 2,3-cis- and trans-disubstituted indolines. The precursors are readily prepared by phase-transfer-catalyzed Michael addition of a glycine Schiff base to a variety of acceptors. When the more reactive alkylidene malonate Michael acceptors are implemented, a one-pot three-component coupling is possible. The net result is a convergent [3 + 2] coupling strategy fo ...[more]

PMID: 18351776

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