| 摘要 |
1286340 Bisphenol methanes UNION RHEINISCHE BRAUNKOHLEN KRAFTSTOFFAG 3Novl970 [27 Dec 1969] 52130/70 Heading C2C Bis - (2 - hydroxy - 3,5 - dimethylphenyl)- alkyl- and -aryl-methane are prepared by reacting 2,4-dimethyl phenol, in pure form or in admixture with one or more other dimethyl phenols, with an aliphatic or aromatic aldehyde containing 1-12 carbon atoms in the presence of a small catalytically active quantity of an acid in a solvent which forms an azeotropic mixture with water, in which solvent the required compound is substantially insoluble in the absence of heat but in which the secondary products are highly soluble, removing all or some of the water of reaction by distillation, on completion of the reaction at a temperature at which a homogeneous solution is obtained, extracting the acid from the reaction mixture with water, neutralizing the residual solution, leaving it to cool and isolating the precipitated product. |
