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Phosphine-free palladium-catalyzed allene carbopalladation/allylic alkylation domino sequence: a new route to 4-(alpha-styryl) gamma-lactams. | LitMetric

Free to decide: Various 4-(alpha-styryl) gamma-lactams are synthesized in 61-88% yield by a phosphine-free palladium-catalyzed carbopalladation/allylic alkylation domino sequence (see scheme). The cyclization is totally regio- and diastereoselective in favor of the 3,4-trans-disubstituted gamma-lactam. The process is successfully applied to the synthesis of a new aza analogue of the naturally occurring lignan (+)-oxo-parabenzlactone.

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http://dx.doi.org/10.1002/chem.200900184DOI Listing

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