Patent Number: 6,794,548

Title: Method of producing 4,4'-biphenol

Abstract: A method for producing 4,4'-biphenol, comprising the steps of: preparing serially arranged reaction bathes for two or more steps; and carrying out a debutylation reaction of 3,3',5,5'-tetra-t-butyl-4,4'-biphenol sequentially in the presence of an acid catalyst in a reaction solvent by supplying at least one kind of phenols selected from the group consisting of phenol, monoalkylphenols, dialkylphenols, and trialkylphenols, in a proportion of at least 0.5 mole part relative to one mole part of 3,3',5,5'-tetra-t-butyl-4,4'-biphenol, to each reaction bath as a solvent for addition, wherein the number of carbon atoms of alkyl groups in alkylphenols consisting of the monoalkylphenols, dialkylphenols, and trialkylphenols, is each independently in the range of 1 to 4, and wherein a solvent for addition to a reaction bath for the latter step has a smaller average number of alkyl groups than a solvent for addition to a reaction bath for the former step.

Inventors: Kawahara; Mikio (Wakayama, JP), Kitaura; Toyokazu (Wakayama, JP)

Assignee: Honschu Chemical Industry Co., Ltd.

International Classification: C07C 37/00 (20060101); C07C 37/50 (20060101); C07C 039/12 ()

Expiration Date: 09/21/2021