Palladium‐catalyzed asymmetric allylic alkylation(AAA)of vinyl benzoxazinanones has become an important strategy for the synthesis of chiral nitrogen‐containing heterocycle compounds.However,the asymmetric synthesis...Palladium‐catalyzed asymmetric allylic alkylation(AAA)of vinyl benzoxazinanones has become an important strategy for the synthesis of chiral nitrogen‐containing heterocycle compounds.However,the asymmetric synthesis of linear‐selective products has rarely been reported.The simultaneous control of regio‐,E/Z‐and enantioselectivities constitutes a major challenge and inhibits the advancement of this chemistry.Herein,we present a palladium‐catalyzed AAA of vinyl benzoxazinanones withα‐thiocyanato ketones,affording various chiral thiocyanates characterized with high linear‐,E‐and stereoselectivities.The reaction has a broad substrate scope and the chiral thiocyanates can be transformed to useful heterocycles.Experimental and computational studies suggest an inner‐sphere mechanism for AAA process,which results from the acidic and coordination effect of the nucleophilic substrates with palladium catalyst.展开更多
文摘Palladium‐catalyzed asymmetric allylic alkylation(AAA)of vinyl benzoxazinanones has become an important strategy for the synthesis of chiral nitrogen‐containing heterocycle compounds.However,the asymmetric synthesis of linear‐selective products has rarely been reported.The simultaneous control of regio‐,E/Z‐and enantioselectivities constitutes a major challenge and inhibits the advancement of this chemistry.Herein,we present a palladium‐catalyzed AAA of vinyl benzoxazinanones withα‐thiocyanato ketones,affording various chiral thiocyanates characterized with high linear‐,E‐and stereoselectivities.The reaction has a broad substrate scope and the chiral thiocyanates can be transformed to useful heterocycles.Experimental and computational studies suggest an inner‐sphere mechanism for AAA process,which results from the acidic and coordination effect of the nucleophilic substrates with palladium catalyst.
