摘要:
A process for separating off poorly soluble by-products from reaction mixtures which are produced in the oxidation of p-cresol with oxygen or an oxygen-containing gas in methanol as solvent in the presence of alkali metal hydroxide and in the presence of metal compounds as catalyst, is characterized in that, after the oxidation, excess alkali is neutralized to the extent that a salt precipitate forms and this salt precipitate is separated off together with the poorly soluble by-products.
摘要:
The new process for preparing 4,4'-dinitrostilbene-2,2'-disulphonic acid and salts thereof by oxidation of 4-nitrotoluene-2-sulphonic acid with an oxidant in the presence of strong bases is characterized in that the oxidation is carried out in a mixture of water and an organic solvent selected from the group consisting of alcohols, ethers and mixtures thereof.
摘要:
The new process for the preparation of 2-nitrobenzaldehydes of the general formula ##STR1## in which X.sub.1 and X.sub.2 either independently of one another represent hydrogen or halogen or one of the substituents represents nitro and the other substituent then represents hydrogen,by oxidation of 2-nitrotoluenes of the general formula ##STR2## in which X.sub.1 and X.sub.2 have the meaning indicated above is characterized in that the oxidation with oxygen or an oxygen-containing gas is carried out in the presence of at least one alkoxyalkylamine as a solvent and in the presence of strong bases.
摘要:
o-Hydroxy-benzaldehydes can be obtained by oxidation of the o-cresols, on which they are based, with oxygen in the presence of substances having a base reaction in a solvent if chelate complexes of iron, manganese or a mixuture of both with polyaza-macrocycles as chelating agents are employed as catalysts. Copper or a copper compound is advantageously added as a co-catalyst.
摘要:
Diphenylamine can be dehydrocyclized on noble metal catalysts in the liquid phase at temperatures of 200.degree. to 340.degree. C. The reaction proceeds with a surprisingly high selectivity.
摘要:
A process for the preparation of a compound of the formula ##STR1## in which R is hydrogen, alkoxy, alkylamino, dialkylamino or an optionally substituted radical from the group consisting of alkyl, cycloalkyl, aralkyl and aryl,R.sup.1 is an optionally substituted radical from the group consisting of alkyl, alkoxy, alkylthio, mono- or dialkylamino and phenyl,R.sup.2 is optionally substituted alkyl, andY is oxygen or sulphur,comprising(a1) reacting a compound of the formula ##STR2## with ##STR3## or withR.sup.5 COOHin whichR.sup.5 is R except for hydrogen, or equivalent, to produce ##STR4## oxidizing that compound or its salt to ##STR5## and phosphorylating. Several of the intermediates are new.
摘要:
p-Hydroxy-benzaldehydes can be obtained by oxidation of the corresponding p-cresols with oxygen in the presence of basic substances in a solvent, the reaction being carried out in the additional presence of a chelate complex of iron and/or manganese. If desired, the reaction can be carried out in the presence of further metal salts.
摘要:
The present invention relates to a novel process for the preparation of cis-1-ammonium-4-alkoxycyclohexanecarbonitrile salts and to novel intermediates or starting compounds which are passed through or used in the process according to the invention.
摘要:
A process is described for producing 2-chloroallyl isothiocyanate from 2,3-dichloro-1-propene by reacting the 2,3-dichloro-1-propene with a thiocyanate in the presence of a phase transfer catalyst, without diluent or in the presence of up to 15 percent by weight based on 2,3-dichloropropene and simultaneously in the presence of an excess of from 10 to 200 mol percent of 2,3-dichloro-1-propene based on the thiocyanate. A process starting from 1,2,3-trichloropropane is also described.
摘要:
Process for preparing cis-alkoxy-substituted spirocyclic 1-H-pyrrolidine-2,4-dione derivatives and alkali metal salts and alkaline earth metal salts thereof.