Synthesis of Some o-Substituted Benzoic Anhydrides

Abstract

Some o-substituted benzoic anhydrides were synthesized from corresponding o-substituted benzoic acid and acetic anhydride by the ordinary method.o-Chlorobenzoic anhydrids (mp 79~80℃)(Ⅰ) was obtained in yield of 91.4% by the reaction of o-Chlorobenzoic acid and acetic anhydride. Similarly， o-Nitrobenzoic anhydride (mp 133~50℃) (Ⅱ) was obtained in yield of 42% and o-acetoxybenzoic anhydride (acetylsalicy1ica anhydride，mp 83~40℃) (Ⅲ)，in yield of 55.2%. In order to confirm the formation ofⅠ,Ⅱ and Ⅲ, accordingly,they were converted into corresponding acidamides, o-Chlorobenzamide (mp 139~140℃，yield 95%)， o-nitrobenzamide (mp 173~50℃，yield 95.2%) and salicylamide (mp 138~138.5℃，yield 75%) were obtained respectively from Ⅰ,Ⅱ and Ⅲ by warming with 28% aqueous ammonia