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Nickel-catalyzed Negishi cross-coupling reactions of secondary alkylzinc halides and aryl iodides.

ABSTRACT: A general Ni-catalyzed process for the cross-coupling of secondary alkylzinc halides and aryl/heteroaryl iodides has been developed. This is the first process to overcome the isomerization and ?-hydride elimination problems that are associated with the use of secondary nucleophiles, and that have limited the analogous Pd-catalyzed systems. The impact of salt additives was also investigated. It was found that the presence of LiBF(4) dramatically improves both isomeric retention and yield for challenging substrates.

SUBMITTER: Joshi-Pangu A

PROVIDER: S-EPMC6474776 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature

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Nickel-catalyzed Negishi cross-coupling reactions of secondary alkylzinc halides and aryl iodides.

Joshi-Pangu Amruta A Ganesh Madhu M Biscoe Mark R MR

Organic letters 20110210 5

A general Ni-catalyzed process for the cross-coupling of secondary alkylzinc halides and aryl/heteroaryl iodides has been developed. This is the first process to overcome the isomerization and β-hydride elimination problems that are associated with the use of secondary nucleophiles, and that have limited the analogous Pd-catalyzed systems. The impact of salt additives was also investigated. It was found that the presence of LiBF(4) dramatically improves both isomeric retention and yield for chal ...[more]

PMID: 21309529

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