HF–Pyridine: A Versatile Promoter for Monoacylation/Sulfonylation of Phenolic Diols and for Direct Conversion of t-Butyldimethylsilyl Ethers to the Corresponding Acetates
Cu(OTf)2 was found to be an efficient catalyst in the acylation reaction of alcohols, phenols, amines and thiols with acetic anhydride in CH2Cl2 or acetic acid. A catalytic cycle has been proposed for the acylation reaction.
A process for producing aromatic polyester which comprises: mixing 5 to 70 mol % (as calculated by converting the repeating unit mentioned below into one molecule) of polyethylene terephthalate (A) with repeating unit represented by a formula (I),
having an inherent viscosity at 30 °C of 0.05 to 1.5 dl/g in an equal weight mixed solvent of tetrachloroethane and phenol, and 95 to 30 mol % of an acyloxyl benzoic acid (B) represented the general formula (II),
with 0.1 to 20 mol % based on the total amount of (A) and (B), of a diacyloxy aromatic compound (C) represented by general formula (III),
and reacting the resulting mixture. The aromatic polyester is excellent in elasticity and mechanical strength, as well as toughness.