METHOD OF PRODUCING 2,3-DIALKYL-1,4-DICYCLOPROPYL-1,4-BUTANEDIONES Russian patent published in 2015 - IPC C07C49/293 C07C45/45 C07C45/00 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing 2,3-dialkyl-1,4-dicyclopropyl-1,4-butanediones of general formula (1):

,

where R=C₂H₅, C₃H₇, C₄H₉, which can be used as initial synthons for synthesis of furans and pyrols in order to produce biologically active compounds for medical and agricultural purposes. The method includes reacting dialkyl acetylene of general formula R-C≡C-R, where R is as indicated above, with twofold excess methyl ether of cyclopropanecarboxylic acid and ethylaluminum dichloride (EtAlCl₂) in the presence of magnesium (Mg, powder) and a Cp₂TiCl₂ catalyst in molar ratio RC≡CR:C₃H₅CO₂CH₃:EtAlCl₂:Mg:Cp₂TiCl₂=10:20:(20-30):(10-14):(0.8-1.2), in tetrahydrofuran in an argon atmosphere at 60°C and atmospheric pressure for 4-8 hours.

EFFECT: method enables to obtain the desired products with output of 58-72%.

1 tbl, 11 ex