acetic / propionic anhydride from NaO(Me)Ac + TsCl

[psyloxy]

Patent DE123052

Ac₂O

382 parts by weiht of TsCl are well mixed with 328 parts of dry NaOAc and heated / cooled by a reflux condenser. Temperature quickly rises to 140°C. After a couple of hours the produced Ac₂O is distilled from the salt mass .

MeAc₂O
Equal parts TsCl and sodium propionate are well mixed and held refluxing at ~150°C for multiple hours. The propionic anhydride is  removed by vac. distillation.

There's also methods for the preparation of AcCl, salicylic acid chloride and benzoic acid anhydride in the patent.

--psyloxy--
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