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Rhodium(I)-catalyzed allenic carbocyclization reaction affording delta- and epsilon-lactams.

ABSTRACT: This letter extends the scope of the rhodium(I)-catalyzed allenic Alder-ene carbocyclization reaction to the preparation of delta- and epsilon-lactams from amides. A variety of allenic propiolamides were cycloisomerized to give a number of unsaturated delta-lactams. In addition, allenic propargylamides give good yields of the corresponding epsilon-lactams. Formation of lactams possessing these ring sizes has rarely been accomplished via transition-metal-catalyzed carbon-carbon bond forming strategies. Thus, this approach provides an alternative strategy for synthesizing these substructures. [reaction: see text].

SUBMITTER: Brummond KM

PROVIDER: S-EPMC3266663 | biostudies-literature | 2007 Jan

REPOSITORIES: biostudies-literature

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Rhodium(I)-catalyzed allenic carbocyclization reaction affording delta- and epsilon-lactams.

Brummond Kay M KM Painter Thomas O TO Probst Donald A DA Mitasev Branko B

Organic letters 20070101 2

This letter extends the scope of the rhodium(I)-catalyzed allenic Alder-ene carbocyclization reaction to the preparation of delta- and epsilon-lactams from amides. A variety of allenic propiolamides were cycloisomerized to give a number of unsaturated delta-lactams. In addition, allenic propargylamides give good yields of the corresponding epsilon-lactams. Formation of lactams possessing these ring sizes has rarely been accomplished via transition-metal-catalyzed carbon-carbon bond forming strat ...[more]

PMID: 17217301

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