GB1313360A - Rearrangement of aralkyl hydroperoxides to form phenols and carbonyl compounds - Google Patents

Abstract

1313360 Phenols SIGNAL CHEMICAL CO 21 Oct 1970 [29 Oct 1969] 49974/70 Heading C2C Phenolic compounds are prepared by continuously contacting an aralkyl hydroperoxide of the general formula where Ar is a substituted or unsubstituted phenyl radical or a polynuclear aromatic radical, R and R<SP>1</SP> are alkyl, cycloalkyl or hydrogen and n is an integer from 1 to 6 inclusive, in a reactor in the presence of a non- reactive organic solvent or carrier, with from 0À1 to 5% by weight, based on the total weight of contacted components, of an acid cleavage catalyst, flowing the contacted components through the reactor at a temperature of from 50 to 120‹ C. and a pressure sufficient to prevent vaporization within the reaction chamber to effect at least 90% cleavage of the hydroperoxide to its corresponding phenolic compound, the residence time in the reactor being not substantially longer than that required to effect the cleavage, the reactor being such that the hold back value of the reaction mixture in the reaction zone is less than 1/e to control the formation of highly coloured side products, and continuously recovering the cleavage product. The reactor is preferably an elongated tubular reactor with a reaction mixture residence time of 5 to 12 minutes. The preferred starting material is p-diisopropylbenzene dihydroperoxide which may be prepared by the oxidation of p-diisopropyl-benzene with molecular oxygen in the presence of aqueous sodium carbonate.