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Enantioselective Aza-Sakurai Cyclizations: Dual Role of Thiourea as H-Bond Donor and Lewis Base.

ABSTRACT: An enantioselective, catalytic aza-Sakurai cyclization of chlorolactams has been developed as an efficient entry into indolizidine and quinolizidine frameworks. Structure-enantioselectivity relationship studies and mechanistic analysis point to a dual role of the catalyst wherein the thiourea moiety of the catalyst is engaged in both anion binding and Lewis base activation of a substrate.

SUBMITTER: Park Y

PROVIDER: S-EPMC5148636 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Enantioselective Aza-Sakurai Cyclizations: Dual Role of Thiourea as H-Bond Donor and Lewis Base.

Park Yongho Y Schindler Corinna S CS Jacobsen Eric N EN

Journal of the American Chemical Society 20161103 45

An enantioselective, catalytic aza-Sakurai cyclization of chlorolactams has been developed as an efficient entry into indolizidine and quinolizidine frameworks. Structure-enantioselectivity relationship studies and mechanistic analysis point to a dual role of the catalyst wherein the thiourea moiety of the catalyst is engaged in both anion binding and Lewis base activation of a substrate. ...[more]

PMID: 27787993

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