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Unconventional Bifunctional Lewis-Bronsted Acid Activation Mode in Bicyclic Guanidine-Catalyzed Conjugate Addition Reactions.

ABSTRACT: DFT calculations have demonstrated that the unconventional bifunctional Brønsted-Lewis acid activation mode is generally applicable to a range of nucleophilic conjugate additions catalyzed by bicyclic guanidine catalysts. It competes readily with the conventional bifunctional Brønsted acid mode of activation. The optimal pro-nucleophiles for this unconventional bifunctional activation are acidic substrates with low pKa, while the best electrophiles are flexible 1,4-diamide and 1,4-diester conjugated systems.

SUBMITTER: Cho B

PROVIDER: S-EPMC6331857 | biostudies-other | 2015 Aug

REPOSITORIES: biostudies-other

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Unconventional Bifunctional Lewis-Brønsted Acid Activation Mode in Bicyclic Guanidine-Catalyzed Conjugate Addition Reactions.

Cho Bokun B Wong Ming Wah MW

Molecules (Basel, Switzerland) 20150818 8

DFT calculations have demonstrated that the unconventional bifunctional Brønsted-Lewis acid activation mode is generally applicable to a range of nucleophilic conjugate additions catalyzed by bicyclic guanidine catalysts. It competes readily with the conventional bifunctional Brønsted acid mode of activation. The optimal pro-nucleophiles for this unconventional bifunctional activation are acidic substrates with low pKa, while the best electrophiles are flexible 1,4-diamide and 1,4-diester conjug ...[more]

PMID: 26295222

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