Acetalization indium triflate

Indium triiodide catalyzes transesterification processes, e.g. the acylation of alcohols or amines and the conversion of THP ethers to acetates (Scheme 8.143) [187]. Indium triflate is also an efficient catalyst for the acylation of alcohols and amines (Scheme 8.144) [188]. Carboxylates are hydrolyzed to the corresponding carboxylic acids in high yield by microwave-assisted reaction on the surface of moistened silica gel in the presence of indium triiodide (Scheme 8.145) [189]. 

Reactions with otP-Unsaturated Ketones, Nitriles and Nitro-Compomds Such reactions are usually effected using acid (see below), or one of a number of mild Lewis acids, such as scandium iodide (with microwave heating), indium bromide " or hafnium triflate, and can be looked on as an extension of the reactions discussed in 20.1.1.6. In the simplest situation, indole reacts with methyl vinyl ketone in a conjugate fashion in acetic acid/acetic anhydride. ... 

Indium(in) triflate (1 mol %) is an excellent catalyst for the Friedel-Crafts acylation reaction. The addition of 1 equiv of lithium perchlorate to the reaction mixture markedly accelerates the reaction. Thus, under mild conditions, anisole is acylated to give the product in excellent yields (eq 3). Acetic anhydride, acetyl chloride, and isopropenyl acetate can he used as acyl donors. 

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