4,5-Dichlorophthalic acid → 4,5-Dichlorophthalic anhydride

Participants

Reaction Steps

200 g of 4,5-dichlorophthalic acid (851 mmol, M.W. 235) was suspended in 480 ml of acetic anhydride and the solution was heated to reflux for 5 hours. The solution was allowed to cool to room temperature over 2 hours, then cooled to 0° C. and filtered and washed with 100 ml of hexane and dried to provide the title compound with a 92% yield (170 g). M.P. 184° C.-186° C. 1H NMR(CDCI3) : 8.1 (s).

Provenance & Evidence