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Direct, intermolecular, enantioselective, iridium-catalyzed allylation of carbamates to form carbamate-protected, branched allylic amines.

ABSTRACT: The direct reaction between carbamates and achiral allylic carbonates to form branched, conveniently protected primary allylic amines with high regioselectivity and enantioselectivity is reported. This process occurs without base or with 0.5 equiv K(3)PO(4) in the presence of a metalacyclic iridium catalyst containing a labile ethylene ligand. The reactions of aryl-, heteroaryl-, and alkyl-substituted allylic carbonates with BocNH(2), FmocNH(2), CbzNH(2), TrocNH(2), TeocNH(2), and 2-oxazolidinone occur in good yields, with high selectivity for the branched isomer and high enantioselectivities (98% average ee).

SUBMITTER: Weix DJ

PROVIDER: S-EPMC2740486 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature

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Direct, intermolecular, enantioselective, iridium-catalyzed allylation of carbamates to form carbamate-protected, branched allylic amines.

Weix Daniel J DJ Marković Dean D Ueda Mitsuhiro M Hartwig John F JF

Organic letters 20090701 13

The direct reaction between carbamates and achiral allylic carbonates to form branched, conveniently protected primary allylic amines with high regioselectivity and enantioselectivity is reported. This process occurs without base or with 0.5 equiv K(3)PO(4) in the presence of a metalacyclic iridium catalyst containing a labile ethylene ligand. The reactions of aryl-, heteroaryl-, and alkyl-substituted allylic carbonates with BocNH(2), FmocNH(2), CbzNH(2), TrocNH(2), TeocNH(2), and 2-oxazolidinon ...[more]

PMID: 19552468

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