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Monoallylation and benzylation of dicarbonyl compounds with alcohols catalysed by a cationic cobalt(iii) compound.

ABSTRACT: Monoallylation and monoalkylation of diketones and β-keto esters with allylic and benzylic alcohols catalysed by [Cp*Co(CH₃CN)₃][SbF₆]₂ (I) are reported. The method does not require any additive and affords regioselective products. The mechanistic investigations were done by in situ ¹H NMR spectroscopy as well as control experiments. It has been shown that reactions proceed via η³-allyl complex formation or ally ether intermediate. The alkylation takes place via only ether intermediate. The resulting allylated and alkylated products have been used for the synthesis of eleven new trisubstituted pyrazoles and one pyrazolone.

SUBMITTER: Chandra Sau M

PROVIDER: S-EPMC8695336 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Monoallylation and benzylation of dicarbonyl compounds with alcohols catalysed by a cationic cobalt(iii) compound.

Chandra Sau Mohan M Mandal Smita S Bhattacharjee Manish M

RSC advances 20210301 16

Monoallylation and monoalkylation of diketones and β-keto esters with allylic and benzylic alcohols catalysed by [Cp*Co(CH3CN)3][SbF6]2 (I) are reported. The method does not require any additive and affords regioselective products. The mechanistic investigations were done by in situ 1H NMR spectroscopy as well as control experiments. It has been shown that reactions proceed via η3-allyl complex formation or ally ethe ...[more]

PMID: 35423451

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