Phosphorus pentachloride → 4-Bromo-2-(methoxyimino)-3-oxobutanoyl chloride

Participants

Reaction Conditions

Reaction Steps

To a suspension of phosphorous pentachloride (64.91 gm; 0.3113 moles) in dichloromethane (250 ml), cooled to −20° C. was added a solution of 4-bromo-2-methoxyimino-3-oxo butyric acid (66.41 gm; 0.2965 moles; purity ca. 97%; containing<0.5% of di- and poly-brominated compounds and prepared as per the method disclosed in WO 03/045899) in dichloromethane (250 ml) over a period of 30 minutes at −20° C. to −5° C. The temperature was raised to 5 to 10° C. and the reaction mixture purged with nitrogen gas for one to two hours to expel out hydrogen chloride gas. The solution containing 4-bromo-2-methoxyimino-3-oxo butyric acid chloride (IV) was cooled to −10° C.

Provenance & Evidence