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Rh-Catalyzed reductive Mannich-type reaction and its application towards the synthesis of (±)-ezetimibe.

ABSTRACT: An effective synthesis for syn-?-lactams was achieved using a Rh-catalyzed reductive Mannich-type reaction. A rhodium-hydride complex (Rh-H) derived from diethylzinc (Et2Zn) and a Rh catalyst was used for the 1,4-reduction of an ?,?-unsaturated ester to give a Reformatsky-type reagent, which in turn, reacted with an imine to give the syn-?-lactam. Additionally, the reaction was applied to the synthesis of (±)-ezetimibe, a potent ?-lactamic cholesterol absorption inhibitor.

SUBMITTER: Isoda M

PROVIDER: S-EPMC4979637 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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Rh-Catalyzed reductive Mannich-type reaction and its application towards the synthesis of (±)-ezetimibe.

Isoda Motoyuki M Sato Kazuyuki K Kunugi Yurika Y Tokonishi Satsuki S Tarui Atsushi A Omote Masaaki M Minami Hideki H Ando Akira A

Beilstein journal of organic chemistry 20160727

An effective synthesis for syn-β-lactams was achieved using a Rh-catalyzed reductive Mannich-type reaction. A rhodium-hydride complex (Rh-H) derived from diethylzinc (Et2Zn) and a Rh catalyst was used for the 1,4-reduction of an α,β-unsaturated ester to give a Reformatsky-type reagent, which in turn, reacted with an imine to give the syn-β-lactam. Additionally, the reaction was applied to the synthesis of (±)-ezetimibe, a potent β-lactamic cholesterol absorption inhibitor. ...[more]

PMID: 27559413

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