Hydrochloric Acid → Momfluorothrin

Participants

Reaction Steps

Under nitrogen atmosphere, 0.54 g of diethyl (1-cyanoethyl) phosphonate was dissolved in 6 ml of tetrahydrofuran and 2.8 ml of a tetrahydrofuran solution of sodium bis(trimethylsilyl)amide (1 mol/l) were added thereto at about 0° C. The mixture was stirred for 30 minutes and 2 ml of a tetrahydrofuran solution containing 1.0 g of 4-methoxymethyl-2,3,5,6-tetrafluorobenzyl 3-formyl-2,2-dimethylcyclopropanecarboxylate given by formula (7): (prepared by the method described as reference production example 1 below) was added thereto and stirred for 3 hours at room temperature. After that, the reaction mixture was poured into about 20 ml of 1% hydrochloric acid and extracted with 100 ml of ethyl acetate. The organic layer was washed with saturated aqueous sodium hydrogencarbonate solution and saturated brine, subsequently, dried over anhydrous sodium sulfate and concentrated under reduced pressure. The obtained residue was subjected to silica gel column chromatography to give 0.76 g of 4-methoxymethy-2,3,5,6-tetrafluorobenzyl 3-(2-cyano-1-propenyl)-2,2-dimethylcyclopropanecarboxylate given by formula (8): (isomers ratio based on the double bond: Z/E=about 2/1).

Provenance & Evidence