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Enantioselective Tail-to-Head Cyclizations Catalyzed by Dual-Hydrogen-Bond Donors.

ABSTRACT: Chiral urea derivatives are shown to catalyze enantioselective tail-to-head cyclization reactions of neryl chloride analogues. Experimental data are consistent with a mechanism in which π-participation by the nucleophilic olefin facilitates chloride ionization and thereby circumvents simple elimination pathways. Kinetic and computational studies support a cooperative mode of catalysis wherein two molecules of the urea catalyst engage the substrate and induce enantioselectivity through selective transition state stabilization.

SUBMITTER: Kutateladze DA

PROVIDER: S-EPMC7293861 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Asymmetric Nazarov Cyclizations of Unactivated Dienones by Hydrogen-Bond-Donor/Lewis Acid Co-Catalyzed, Enantioselective Proton-Transfer.

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