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Total synthesis of indolizidine alkaloid (-)-209D: overriding substrate bias in the asymmetric rhodium-catalyzed [2+2+2] cycloaddition.

ABSTRACT: CO! You had me at hello: The use of chiral biphenyl-based phosphoramidite ligands on rhodium provides an efficient [2+2+2] cycloaddition between terminal alkyl alkynes and alkenyl isocyanates (see scheme). The cycloaddition proceeds through a CO migration pathway, and facilitates a rapid four-step asymmetric synthesis of indolizidine (-)-209D.

SUBMITTER: Yu RT

PROVIDER: S-EPMC2747357 | biostudies-literature | 2009

REPOSITORIES: biostudies-literature

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Total synthesis of indolizidine alkaloid (-)-209D: overriding substrate bias in the asymmetric rhodium-catalyzed [2+2+2] cycloaddition.

Yu Robert T RT Lee Ernest E EE Malik Guillaume G Rovis Tomislav T

Angewandte Chemie (International ed. in English) 20090101 13

CO! You had me at hello: The use of chiral biphenyl-based phosphoramidite ligands on rhodium provides an efficient [2+2+2] cycloaddition between terminal alkyl alkynes and alkenyl isocyanates (see scheme). The cycloaddition proceeds through a CO migration pathway, and facilitates a rapid four-step asymmetric synthesis of indolizidine (-)-209D. ...[more]

PMID: 19229912

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