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Activation of alcohols with carbon dioxide: intermolecular allylation of weakly acidic pronucleophiles.

ABSTRACT: The direct coupling of allyl alcohols with nitroalkanes, nitriles, and aldehydes using catalytic Pd(PPh3)4 has been accomplished via activation of C-OH bonds with CO2. The in situ formation of carbonates from alcohols and CO2 facilitates oxidative addition to Pd to form reactive ?-allylpalladium intermediates. In addition, the formation of a strong base activates nucleophiles toward the reaction with the ?-allylpalladium electrophile. Overall, this atom economical reaction provides a new C-C bond without the use of an external base and generates water as the only byproduct.

SUBMITTER: Lang SB

PROVIDER: S-EPMC4136682 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Activation of alcohols with carbon dioxide: intermolecular allylation of weakly acidic pronucleophiles.

Lang Simon B SB Locascio Theresa M TM Tunge Jon A JA

Organic letters 20140804 16

The direct coupling of allyl alcohols with nitroalkanes, nitriles, and aldehydes using catalytic Pd(PPh3)4 has been accomplished via activation of C-OH bonds with CO2. The in situ formation of carbonates from alcohols and CO2 facilitates oxidative addition to Pd to form reactive π-allylpalladium intermediates. In addition, the formation of a strong base activates nucleophiles toward the reaction with the π-allylpalladium electrophile. Overall, this atom economical reaction provides a new C-C bon ...[more]

PMID: 25089846

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