Acetic anhydride zinc chloride

The commonest system for bringing about acetolysis, which will be regarded as being the cleavage of an 0-R bond with concomitant formation of an acetic ester, is acetic anhydride-sulfuric acid. Other systems that have been used to a lesser extent are acetic anhydride-perchloric acid, acetic anhydride-zinc chloride, or trifluoroacetio anhydride-acetic acid. All of these species give rise to the acetylium ion, nCH3CO]+, which is the attacking species in all of these reactions. 

Anjaneyulu, A. S. R., Mallavadhani, U. V., Venkateswarlu, Y., and Ramaprasad, A. V. 1987. Reaction of acetic anhydride/zinc chloride reagent with phenols improved yields of hydroxyacetophenones. Ind. J. Chem. 26B 823-826. 

Acetic anhydride zinc chloride (CH3CO)aO/ZnCls... 

Acetylation of tomatidenol (101) with acetic anhydride-zinc chloride-acetic acid yielded the azomethine 127, the reaction of which with selenium... 

Acetylation of solafloridine (41) with acetic anhydride-zinc chloride-acetic acid or photolysis of iV-nitrosodihydrosolafloridine diacetate (142) furnished the diacetate 143. Subsequent oxidation with manganese dioxide in CHCI3 at room temperature yielded ketone 144, which was reduced with sodium borohydride, without purification, to the piperidinol 145 (yield from 143 55%). As a by-product of the Mn02 oxidation of 143, the pyridyl steroid 146 was isolated. 

The role of various conformers has been discussed in detail for the acetylation of 1,4-dialkylcyclohexene using acetic anhydride-zinc chloride. Typically the pro-... 

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