摘要:
Phenols are oxidated to quinones with hydrogen peroxide in the presence of catalytic amounts of bromine, iodine, hydrogen bromide and hydrogen iodide.
摘要:
Process industrially and economically useful for preparing difunctional aliphatic organic compounds of formulaX-(CH.sub.2).sub.n -Yin which n=6,7, X=--COOH, --COOR, Y=--CN, --COOH, --CONH.sub.2, --CH.sub.2 --NH.sub.2 --COOR wherein R is a linear or branched alkyl containing 1-6 carbon atoms.The process starts from a ketone of the formula ##STR1## in which n=2,3 and R.sub.1 =--CN, --COOH. The ketone (I) is changed to the corresponding hydroperoxide by means of H.sub.2 O.sub.2, the hydroperoxide is catalytically split by means of a catalyst Fe.sup.++ /Cu.sup.++ to give an unsaturated acid of the formulaHOOC--(CH.sub.2).sub.3 --CH.dbd.CH--(CH.sub.2).sub.2 -R.sub.1and this is catalytically hydrogenated to the compoundHOOC--(CH.sub.2).sub.n -R.sub.1When R.sub.1 is different from Y, R.sub.1 is changed to Y through known methods.
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:
A process for the production of benzofuran derivatives having the general formula, ##STR1## wherein R is alkyl, in particular of 2,3-dihydro-2,2-dimethyl benzofuran-7-ol, starting from pyrocatechol ethers in one step operation.The process essentially consists of heating a solution of pyrocatechol ether in an inert organic solvent in the presence of a catalyst comprising metals of 3.degree. and 4.degree. group of the Periodic System in form of carboxylates or of modified zeolites.The products are known intermediates for the production of insecticides.
摘要:
A process for preparing o-isopropoxyphenol (I) by means of the reaction: ##STR1## in which X is a halogen atom and in which the pyrocatechol (II) is reacted with the isopropyl halide (III) in the presence of an alkaline base in the solid state and of a solid-liquid phase transfer catalyst, in a reaction medium constituted by one or more organic solvents.The catalyst is constituted by a quaternary ammonium or phosphonium salt.The reaction is conducted in a nitrogen atmosphere, at atmospheric pressure, under agitation, at a temperature of preferably between 50.degree. C. and 130.degree. C.
摘要:
A process is described for preparing 2,3-dihydro-2,2-dimethylbenzofuran-7-ol (I), which is a useful intermediary in the preparation of Carbofuran, a known multi-functional insecticide.The process consists essentially of reacting the pyrocatechol and a methallylhalide in an inert organic solvent in the presence of a solid inorganic base and a suitable catalyst, to obtain o.methallyloxyphenol with high conversion and high selectivity; this product is thermally transposed to o.methallylpyrocatechol, which is finally cyclized to the product (I) by heterogeneous catalysis in the presence of solid acid catalysts.All stages of the process can be carried out in a single reaction medium, without separating intermediate products.
摘要:
Process to reduce stereoselectively 3alpha-hydroxy-7-keto-5beta-cholanic acid to 3alpha,7beta-dihydroxy-5beta-cholanic acid in ter.alcohols by using, as reducing agent, sodium metal in the presence of other metal salts.Examples of metal salts particularly useful are: potassium, cesium and rhubidium organic salts and, more particularly, potassium acetate or potassium ter.butylate.
摘要:
Process for the preparation of hydroperoxides of alkylbenzenes characterized by the fact that the alkylbenzene reacts with oxygen in the presence of a catalytic system which includes an N-hydroxyimide or an N-hydroxysulfamide and a polar solvent.
摘要:
A process for the preparation of 5-(2,4-difluorophenyl)-salicylic acid comprising the reaction of an organometallic derivative with a suitable substituted benzene in the presence of a transition-metal based catalyst is described.
摘要:
A process for the selective side-chain halogenation of alkylaromatic hydrocarbons, consisting of reacting the hydrocarbon with an N-halogenoamine in the presence of a proton donor and a metal ion.