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

Article abstract of DOI:10.1039/d0ra09778k

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 byin situ¹H NMR spectroscopy as well as control experiments. It has been shown that reactions proceedviaη³-allyl complex formation or ally ether intermediate. The alkylation takes placeviaonly ether intermediate. The resulting allylated and alkylated products have been used for the synthesis of eleven new trisubstituted pyrazoles and one pyrazolone.