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6-exo-trig Michael addition-lactonizations for catalytic enantioselective chromenone synthesis.

ABSTRACT: The catalytic enantioselective 6-exo-trig Michael addition-lactonization of enone-acid substrates to form cis-chromenones with high diastereo- and enantiocontrol was developed using the commercially available isothiourea tetramisole. An acidic workup proved necessary to minimize product epimerization and maximize product er, providing cis-chromenones in excellent yield, and with excellent diastereo- and enantioselectivity.

SUBMITTER: Neyyappadath RM

PROVIDER: S-EPMC5358503 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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6-exo-trig Michael addition-lactonizations for catalytic enantioselective chromenone synthesis.

Neyyappadath Rifahath M RM Cordes David B DB Slawin Alexandra M Z AM Smith Andrew D AD

Chemical communications (Cambridge, England) 20170201 17

The catalytic enantioselective 6-exo-trig Michael addition-lactonization of enone-acid substrates to form cis-chromenones with high diastereo- and enantiocontrol was developed using the commercially available isothiourea tetramisole. An acidic workup proved necessary to minimize product epimerization and maximize product er, providing cis-chromenones in excellent yield, and with excellent diastereo- and enantioselectivity. ...[more]

PMID: 28133660

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