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Catalytic asymmetric synthesis of 3,2'-pyrrolinyl spirooxindoles via conjugate addition/Schmidt-type rearrangement of vinyl azides and (E)-alkenyloxindoles.

ABSTRACT: A catalytic asymmetric conjugate addition/Schmidt-type rearrangement of vinyl azides and (E)-alkenyloxindoles was realized. It afforded a variety of optically active 3,2'-pyrrolinyl spirooxindoles with high yields (up to 98%), and excellent diastereo- and enantioselectivities (up to 98% ee, >19 : 1 dr), even at the gram-scale in the presence of a chiral N,N'-dioxide-nickel(ii) complex. In addition, a possible catalytic cycle and transition state model were proposed to rationalize the stereoselectivity.

SUBMITTER: Zhong Z

PROVIDER: S-EPMC8162805 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Catalytic asymmetric synthesis of 3,2'-pyrrolinyl spirooxindoles via conjugate addition/Schmidt-type rearrangement of vinyl azides and (E)-alkenyloxindoles.

Zhong Ziwei Z Xiao Zhijie Z Liu Xiaohua X Cao Weidi W Feng Xiaoming X

Chemical science 20200928 42

A catalytic asymmetric conjugate addition/Schmidt-type rearrangement of vinyl azides and (E)-alkenyloxindoles was realized. It afforded a variety of optically active 3,2'-pyrrolinyl spirooxindoles with high yields (up to 98%), and excellent diastereo- and enantioselectivities (up to 98% ee, >19 : 1 dr), even at the gram-scale in the presence of a chiral N,N'-dioxide-nickel(ii) complex. In addition, a possible catalytic cycle and transition state model were proposed to ration ...[more]

PMID: 34094393

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