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Halogen-Metal Exchange on Bromoheterocyclics with Substituents Containing an Acidic Proton via Formation of a Magnesium Intermediate.

ABSTRACT: A selective and practical bromine-metal exchange on bromoheterocyclics bearing substituents with an acidic proton under non-cryogenic conditions was developed by a simple modification of an existing protocol. Our protocol of using a combination of i-PrMgCl and n-BuLi has not only solved the problem of intermolecular quenching that often occurred when using alkyl lithium alone as the reagent for halogen-lithium exchange, but also offered a highly selective method for performing bromo-metal exchange on dibrominated arene compounds through chelation effect.

SUBMITTER: Tian Q

PROVIDER: S-EPMC6150384 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Halogen-Metal Exchange on Bromoheterocyclics with Substituents Containing an Acidic Proton via Formation of a Magnesium Intermediate.

Tian Qingqiang Q Shang Suqin S Wang Huajun H Shi Guoqiang G Li Zhiyao Z Yuan Jianyong J

Molecules (Basel, Switzerland) 20171111 11

A selective and practical bromine-metal exchange on bromoheterocyclics bearing substituents with an acidic proton under non-cryogenic conditions was developed by a simple modification of an existing protocol. Our protocol of using a combination of i-PrMgCl and n-BuLi has not only solved the problem of intermolecular quenching that often occurred when using alkyl lithium alone as the reagent for halogen-lithium exchange, but also offered a highly selective method for performing bromo-metal exchan ...[more]

PMID: 29137130

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