摘要:
Hydroxyaromatic compounds, especially phenols, are reacted with an alkyl tert.butyl ether in the presence of an acidic catalyst and the as formed light alcoholic fractions are removed by flashing.
摘要:
Processs for the hydroxylation of aromatic compounds containing a dioxa-heterocyclic system which comprises directly hydroxlating said compounds with hydrogen peroxide in; the presence of a zeolitic catalyst having the general formula: xTiO2′(1−x)SiO2 wherein x is i a number ranging from 0.0001 to 0.04.
摘要:
Process for the preparation of aromatic compounds containing a heterocyclic system, having general formula (II): ##STR1## which comprises reacting catechol, optionally substituted, with a methylene dihalide in a basic environment and in the presence of a solvent medium consisting of N-methylpyrrolidone.
摘要:
Mono-ethers of hydroquinones of formula (I) ##STR1## wherein R represents alkyl, alkoxy-alkyl, cycloalkyl, aryl-alkyl, or cycloalkyl-alkyl, andR.sup.1 is hydrogen or alkyl, cycloalkyl, aryl-alkyl, or cycloalkyl-alkyl, are prepared by contacting the corresponding hydroquinones with the corresponding alcohols ROH, in the presence of a catalytic mixture consisting of(a) a strong acid(b) a halogen or a hydrohalic acid selected from HBr, HI, I.sub.2, and Br.sub.2, and(c) H.sub.2 O.sub.2 in a molar amount lower than that of the starting hydroquinone.
摘要:
Process for the preparation of ethers of hydroxybenzoic acid having general formula (I), which comprises reacting a hydroxybenzoic acid, optionally substituted, with a halide XR1, wherein X is a halogen such as chlorine, in a basic environment and in an aqueous or aqueous/organic biphasic solvent.