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Iridium Catalyzed Hydro-hydroxyalkylation of Butadiene: Carbonyl Crotylation.

ABSTRACT: Exposure of alcohols 1a-1i to butadiene in the presence of a cyclometallated iridium catalyzed derived from allyl acetate, 4-methoxy-3-nitrobenzoic acid and BIPHEP (2,2'-bis(diphenylphosphino)biphenyl) results in hydrogen transfer to generate aldehyde-allyliridium pairs, which engage in C-C coupling to form products of carbonyl crotylation. Under related conditions using 1,4-butanediol as hydrogen donor, butadiene reductively couples to aldehydes 2e-2g and 2i to furnish carbonyl crotylation products 3e-3g and 3i. Thus, butadiene mediated carbonyl crotylation occurs with equal facility from the alcohol or aldehyde oxidation level with complete levels of branched regioselectivity.

SUBMITTER: Zbieg JR

PROVIDER: S-EPMC3001632 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature

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Iridium Catalyzed Hydro-hydroxyalkylation of Butadiene: Carbonyl Crotylation.

Zbieg Jason R JR Fukuzumi Takeo T Krische Michael J MJ

Advanced synthesis & catalysis 20101001 14-15

Exposure of alcohols 1a-1i to butadiene in the presence of a cyclometallated iridium catalyzed derived from allyl acetate, 4-methoxy-3-nitrobenzoic acid and BIPHEP (2,2'-bis(diphenylphosphino)biphenyl) results in hydrogen transfer to generate aldehyde-allyliridium pairs, which engage in C-C coupling to form products of carbonyl crotylation. Under related conditions using 1,4-butanediol as hydrogen donor, butadiene reductively couples to aldehydes 2e-2g and 2i to furnish carbonyl crotylation prod ...[more]

PMID: 21165157

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