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Bronsted acid and Pd-PHOX dual-catalysed enantioselective addition of activated C-pronucleophiles to internal dienes.

ABSTRACT: We describe the development of Pd-PHOX-catalysed enantioselective couplings of internal dienes with malononitrile and other activated C-pronucleophiles. Reactions are dramatically accelerated by the addition of Et₃N·HBAr^F ₄ as a Brønsted acid co-catalyst, enabling a suite of products bearing a variety of alkyl substituents at the stereogenic carbon to be prepared. A series of mechanism-oriented experiments reveal key aspects of the catalytic cycle and the importance of the non-coordinating BAr^F ₄ counterion in not only promoting reactions of internal dienes but also additions of previously unreactive nucleophiles towards terminal dienes.

SUBMITTER: Park S

PROVIDER: S-EPMC6524568 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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Brønsted acid and Pd-PHOX dual-catalysed enantioselective addition of activated C-pronucleophiles to internal dienes.

Park Sangjune S Adamson Nathan J NJ Malcolmson Steven J SJ

Chemical science 20190417 19

We describe the development of Pd-PHOX-catalysed enantioselective couplings of internal dienes with malononitrile and other activated C-pronucleophiles. Reactions are dramatically accelerated by the addition of Et3N·HBArF 4 as a Brønsted acid co-catalyst, enabling a suite of products bearing a variety of alkyl substituents at the stereogenic carbon to be prepared. A series of mechanism-oriented experiments reveal key aspects of the catalytic cycle and the importa ...[more]

PMID: 31183071

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