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Enantioselective synthesis of polycyclic nitrogen heterocycles by Rh-catalyzed alkene hydroacylation: constructing six-membered rings in the absence of chelation assistance.

ABSTRACT: Catalytic, enantioselective hydroacylations of N-allylindole-2-carboxaldehydes and N-allylpyrrole-2-carboxaldehydes are reported. In contrast to many alkene hydroacylations that form six-membered rings, these annulative processes occur in the absence of ancillary functionality to stabilize the acylrhodium(III) hydride intermediate. The intramolecular hydroacylation reactions generate 7,8-dihydropyrido[1,2-a]indol-9(6H)ones and 6,7-dihydroindolizin-8(5H)-ones in moderate to high yields with excellent enantioselectivities.

SUBMITTER: Du XW

PROVIDER: S-EPMC4144754 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Enantioselective synthesis of polycyclic nitrogen heterocycles by Rh-catalyzed alkene hydroacylation: constructing six-membered rings in the absence of chelation assistance.

Du Xiang-Wei XW Ghosh Avipsa A Stanley Levi M LM

Organic letters 20140714 15

Catalytic, enantioselective hydroacylations of N-allylindole-2-carboxaldehydes and N-allylpyrrole-2-carboxaldehydes are reported. In contrast to many alkene hydroacylations that form six-membered rings, these annulative processes occur in the absence of ancillary functionality to stabilize the acylrhodium(III) hydride intermediate. The intramolecular hydroacylation reactions generate 7,8-dihydropyrido[1,2-a]indol-9(6H)ones and 6,7-dihydroindolizin-8(5H)-ones in moderate to high yields with excel ...[more]

PMID: 25020184

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