Catalysts for Transesterification and Dehydration

Transesterification was used for many decades for the technical syntheses of PET and PBT. The most widely used catalyst is Ti(OBu)4 (or other tetraalkox- 

Ishihara and Yamamoto et al. investigated the catalytic activities of various metal salts for esterification of equimolar aliphatic carboxylic acid and 

Friedel-Crafts aromatic substitution reactions have been widely explored in polymer chemistry [29,30] and generally proceed with Lewis acids such as AICI3 with elimination of hydrogen halides. In superacid solutions, however, the Friedel-Crafts reactions take place with dehydration from the oxygen of the carbonyl group and the proton of aromatics. The reactivity of the pro-tonated carbonyl group in the superacid can be further increased by the 

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