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Enantioselective Intermolecular C-H Functionalization of Allylic and Benzylic sp(3) C-H Bonds Using N-Sulfonyl-1,2,3-triazoles.

ABSTRACT: The enantioselective intermolecular sp(3) C-H functionalization at the allylic and benzylic positions was achieved using rhodium-catalyzed reactions with 4-phenyl-N-(methanesulfonyl)-1,2,3-triazole. The optimum dirhodium tetracarboxylate catalyst for these reactions was Rh2(S-NTTL)4. The rhodium-bound ?-imino carbene intermediates preferentially reacted with tertiary over primary C-H bonds in good yields and moderate levels of enantioselectivity (66-82% ee). This work demonstrates that N-sulfonyltriazoles can be applied to the effective C-H functionalization at sp(3) C-H bonds of substrates containing additional functionality.

SUBMITTER: Kubiak RW

PROVIDER: S-EPMC5521008 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Enantioselective Intermolecular C-H Functionalization of Allylic and Benzylic sp(3) C-H Bonds Using N-Sulfonyl-1,2,3-triazoles.

Kubiak Robert W RW Mighion Jeffrey D JD Wilkerson-Hill Sidney M SM Alford Joshua S JS Yoshidomi Tetsushi T Davies Huw M L HM

Organic letters 20160622 13

The enantioselective intermolecular sp(3) C-H functionalization at the allylic and benzylic positions was achieved using rhodium-catalyzed reactions with 4-phenyl-N-(methanesulfonyl)-1,2,3-triazole. The optimum dirhodium tetracarboxylate catalyst for these reactions was Rh2(S-NTTL)4. The rhodium-bound α-imino carbene intermediates preferentially reacted with tertiary over primary C-H bonds in good yields and moderate levels of enantioselectivity (66-82% ee). This work demonstrates that N-sulfony ...[more]

PMID: 27333162

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