METHOD OF PRODUCING CYCLOPENTANONE Russian patent published in 2012 - IPC C07C49/395 C07C45/67 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing cyclopentanone, which is an active synthone for synthesis of drugs, plant protection agents, fragrant compositions, and is also used as a solvent, a BMC monomer, in production of crystalline wafers and engineering plastics. The method involves liquid-phase isomerisation of 1,2-epoxycyclopentane in the presence of a catalyst in a solvent medium and under gas pressure. The isomerisation reaction takes place in the presence of a homogeneous catalyst in form of concentrated 30-40% solution of a MgBr₂·2H₂O·4N-MP (N-MP = N-methylpyrrolidone) complex in N-methylpyrrolidone, with weight ratio of MgBr₂ in the reaction mixture equal to 2-8%, initial concentration of 1,2-epoxycyclopentane equal to 30-45%, at temperature 110-440°C and gas pressure 0.2-0.5 MPa, where said gas is inert nitrogen, in the medium of a mixed N-methylpyrrolidone/xylene solvent in weight ratio (1.5-2)/1, followed by extraction of the catalyst from the reaction products and further reuse without regeneration.

EFFECT: method enables to obtain the end product with high selectivity.

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