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Organic chemistry. Functionalization of C(sp3)-H bonds using a transient directing group.

ABSTRACT: Proximity-driven metalation has been extensively exploited to achieve reactivity and selectivity in carbon-hydrogen (C-H) bond activation. Despite the substantial improvement in developing more efficient and practical directing groups, their stoichiometric installation and removal limit efficiency and, often, applicability as well. Here we report the development of an amino acid reagent that reversibly reacts with aldehydes and ketones in situ via imine formation to serve as a transient directing group for activation of inert C-H bonds. Arylation of a wide range of aldehydes and ketones at the ? or ? positions proceeds in the presence of a palladium catalyst and a catalytic amount of amino acid. The feasibility of achieving enantioselective C-H activation reactions using a chiral amino acid as the transient directing group is also demonstrated.

SUBMITTER: Zhang FL

PROVIDER: S-EPMC4817545 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Organic chemistry. Functionalization of C(sp3)-H bonds using a transient directing group.

Zhang Fang-Lin FL Hong Kai K Li Tuan-Jie TJ Park Hojoon H Yu Jin-Quan JQ

Science (New York, N.Y.) 20160101 6270

Proximity-driven metalation has been extensively exploited to achieve reactivity and selectivity in carbon-hydrogen (C-H) bond activation. Despite the substantial improvement in developing more efficient and practical directing groups, their stoichiometric installation and removal limit efficiency and, often, applicability as well. Here we report the development of an amino acid reagent that reversibly reacts with aldehydes and ketones in situ via imine formation to serve as a transient directin ...[more]

PMID: 26816374

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