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Primary-tertiary diamine-catalyzed Michael addition of ketones to isatylidenemalononitrile derivatives.

ABSTRACT: Simple primary-tertiary diamines easily derived from natural primary amino acids were used to catalyze the Michael addition of ketones with isatylidenemalononitrile derivatives. Diamine 1a in combination with D-CSA as an additive provided Michael adducts in high yield (up to 94%) and excellent enantioselectivity (up to 99%). The catalyst 1a was successfully used to catalyze the three-component version of the reaction by a domino Knoevenagel-Michael sequence. The Michael adduct 4a was transformed into spirooxindole 6 by a reduction with sodium borohydride in a highly enantioselective manner.

SUBMITTER: Kumar A

PROVIDER: S-EPMC4077384 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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