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A chiral nickel DBFOX complex as a bifunctional catalyst for visible-light-promoted asymmetric photoredox reactions.

ABSTRACT: The enantioselective photoredox reaction of ?,?-unsaturated carbonyl compounds and tertiary/secondary ?-silylamines was enabled by a readily available single NiII-DBFOX catalyst (DBFOX = 4,6-bis((R)-4-phenyl-4,5-dihydrooxazol-2-yl)dibenzo[b,d]furan) under visible light conditions. The non-precious chiral catalyst is involved in the photochemical process to initiate single electron transfer and at the same time provides a well-organized chiral environment for the subsequent radical transformations. Good to excellent enantioselectivities (80-99% ee) were obtained for the formation of chiral ?-amino carboxylic acid derivatives and ?-lactams.

SUBMITTER: Shen X

PROVIDER: S-EPMC5969497 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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A chiral nickel DBFOX complex as a bifunctional catalyst for visible-light-promoted asymmetric photoredox reactions.

Shen Xiang X Li Yanjun Y Wen Zhaorui Z Cao Shi S Hou Xinyi X Gong Lei L

Chemical science 20180427 20

The enantioselective photoredox reaction of α,β-unsaturated carbonyl compounds and tertiary/secondary α-silylamines was enabled by a readily available single NiII-DBFOX catalyst (DBFOX = 4,6-bis((R)-4-phenyl-4,5-dihydrooxazol-2-yl)dibenzo[b,d]furan) under visible light conditions. The non-precious chiral catalyst is involved in the photochemical process to initiate single electron transfer and at the same time provides a well-organized chiral environment for the s ...[more]

PMID: 29899949

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