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Positional Selectivity in C-H Functionalizations of 2-Benzylfurans with Bimetallic Catalysts.

ABSTRACT: Metal-catalyzed carbon-carbon bond-forming reactions are a mainstay in the synthesis of pharmaceutical agents. A long-standing problem plaguing the field of transition metal catalyzed C-H functionalization chemistry is control of selectivity among inequivalent C-H bonds in organic reactants. Herein we advance an approach to direct site selectivity in the arylation of 2-benzylfurans founded on the idea that modulation of cooperativity in bimetallic catalysts can enable navigation of selectivity. The bimetallic catalysts introduced herein exert a high degree of control, leading to divergent site-selective arylation reactions of both sp(2) and sp(3) C-H bonds of 2-benzylfurans. It is proposed that the selectivity is governed by cation-? interactions, which can be modulated by choice of base and accompanying additives [MN(SiMe3)2, M = K or Li·12-crown-4].

SUBMITTER: Zhang J

PROVIDER: S-EPMC4988891 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature

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Positional Selectivity in C-H Functionalizations of 2-Benzylfurans with Bimetallic Catalysts.

Zhang Jiadi J Sha Sheng-Chun SC Bellomo Ana A Trongsiriwat Nisalak N Gao Feng F Tomson Neil C NC Walsh Patrick J PJ

Journal of the American Chemical Society 20160318 12

Metal-catalyzed carbon-carbon bond-forming reactions are a mainstay in the synthesis of pharmaceutical agents. A long-standing problem plaguing the field of transition metal catalyzed C-H functionalization chemistry is control of selectivity among inequivalent C-H bonds in organic reactants. Herein we advance an approach to direct site selectivity in the arylation of 2-benzylfurans founded on the idea that modulation of cooperativity in bimetallic catalysts can enable navigation of selectivity. ...[more]

PMID: 26937718

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