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Chemo- and regioselective C(sp³)-H arylation of unactivated allylarenes by deprotonative cross-coupling.

ABSTRACT: The combination of aryl bromides, allylbenzene, base and a palladium catalyst usually results in a Heck reaction. Herein we combine these same reagents, but override the Heck pathway by employing a strong base. In the presence of LiN(SiMe3)2, allylbenzene derivatives undergo reversible deprotonation. Transmetalation of the resulting allyllithium intermediate to LPdAr(Br) and reductive elimination provide the 1,1-diarylprop-2-enes, which are not accessible by the Heck reaction. The regioselectivity in this deprotonative cross-coupling process is catalyst-controlled and very high.

SUBMITTER: Hussain N

PROVIDER: S-EPMC4038169 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature

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Chemo- and regioselective C(sp³)-H arylation of unactivated allylarenes by deprotonative cross-coupling.

Hussain Nusrah N Frensch Gustavo G Zhang Jiadi J Walsh Patrick J PJ

Angewandte Chemie (International ed. in English) 20140226 14

The combination of aryl bromides, allylbenzene, base and a palladium catalyst usually results in a Heck reaction. Herein we combine these same reagents, but override the Heck pathway by employing a strong base. In the presence of LiN(SiMe3)2, allylbenzene derivatives undergo reversible deprotonation. Transmetalation of the resulting allyllithium intermediate to LPdAr(Br) and reductive elimination provide the 1,1-diarylprop-2-enes, which are not accessible by the Heck reaction. The regioselectivi ...[more]

PMID: 24574070

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