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Nickel-catalyzed carbon-carbon bond-forming reactions of unactivated tertiary alkyl halides: Suzuki arylations.

ABSTRACT: The first Suzuki cross-couplings of unactivated tertiary alkyl electrophiles are described. The method employs a readily accessible catalyst (NiBr(2)·diglyme/4,4'-di-tert-butyl-2,2'-bipyridine, both commercially available) and represents the initial example of the use of a group 10 catalyst to cross-couple unactivated tertiary electrophiles to form C-C bonds. This approach to the synthesis of all-carbon quaternary carbon centers does not suffer from isomerization of the alkyl group, in contrast with the umpolung strategy for this bond construction (cross-coupling of a tertiary alkylmetal with an aryl electrophile). Preliminary mechanistic studies are consistent with the generation of a radical intermediate along the reaction pathway.

SUBMITTER: Zultanski SL

PROVIDER: S-EPMC3547142 | biostudies-literature | 2013 Jan

REPOSITORIES: biostudies-literature

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Nickel-catalyzed carbon-carbon bond-forming reactions of unactivated tertiary alkyl halides: Suzuki arylations.

Zultanski Susan L SL Fu Gregory C GC

Journal of the American Chemical Society 20130102 2

The first Suzuki cross-couplings of unactivated tertiary alkyl electrophiles are described. The method employs a readily accessible catalyst (NiBr(2)·diglyme/4,4'-di-tert-butyl-2,2'-bipyridine, both commercially available) and represents the initial example of the use of a group 10 catalyst to cross-couple unactivated tertiary electrophiles to form C-C bonds. This approach to the synthesis of all-carbon quaternary carbon centers does not suffer from isomerization of the alkyl group, in contrast ...[more]

PMID: 23281960

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