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

Participants

Reaction Conditions

Reaction Steps

4-bromo-2-methoxyimino-3-oxobutyric acid (2.57 g) is added to methylene chloride (20 ml) and the solution is cooled to −20° C. Phosphorous pentachloride (2.5 g) is added in small lots over a period of 5 min while maintaining the temperature between −20° C. and −15° C. Thereafter, the temperature is slowly raised to −5° C. and the reaction mass is stirred at −5° C. to 0° C. until the starting material's absence is noted with TLC in about 30 mins. Aqueous workup was done to remove inorganic impurities and byproducts and the organic layer was dried over anhydrous sodium sulfate. This solution is taken as is for the next stage.

Provenance & Evidence