Abstract:
Bis- and tris-(3-dimethylaminopropyl)-amine can be prepared by catalytic hydrogenation of 3-(dimethylamino)-propionitrile with a palladium catalyst on an Al.sub.2 O.sub.3 -containing support.
Abstract:
Aromatic and aliphatic aldehydes can be prepared from the corresponding aromatic or aliphatic carboxylic acids or the esters, anhydrides or halides thereof at elevated temperature by catalytic gas phase hydrogenation using hydrogen if use is made of a catalyst system composed of oxides of titanium and/or vanadium and of one or more co-metals, the co-metals being selected from the group consisting of chromium, molybdenum, cobalt, nickel, zinc, cadmium and copper.
Abstract:
m-Chlorotoluene is removed from chlorotoluene mixtures with a content of up to 10% by weight of m-chlorotoluene, with reference to the total amount of chlorotoluene in the mixture, by chlorinating a substantially toluene-free chlorotoluene mixture in the presence of a Friedel-Crafts catalyst and if appropriate a co-catalyst at from 0.degree. C. up to the boiling point of the mixture, until the content of m-chlorotoluene has decreased to a value of
Abstract:
In a process for the preparation of an aryloxyacetic acid by oxidation of aryloxyethanol of the formula ##STR1## wherein m represents 1 or 2,n represents the numeral which results from the difference (6-m) andR either individually or independently of one another represent hydrogen, alkyl, cycloalkyl, aryl, aralkyl, alkoxy, cycloalkoxy, aryloxy, hydroxyl, halogen, alkylcarbonyl, arylcarbonyl, carboxyl or nitro, or represent a benzene ring or cycloalkane ring fused to the phenyl ring,with oxygen or an oxygen-containing gas in an aqueous alkaline medium at a temperature from 0.degree. C. to the boiling point of the reaction mixture in the presence of platinum metals and/or palladium metals containing catalyst, the improvement which comprises carrying out the oxidation in the additional presence of an activator of lead and/or bismuth and/or a compound thereof and optionally in the additional presence of Cadmium and/or its compounds.
Abstract:
Novel process for the preparation of an arylglyoxylic acid compound, e.g., phenylglyoxylic acid, which comprises oxidizing an .alpha.-hydroxyarylacetic acid, e.g., mandelic acid, of the formula ##STR1## in which m is 1, 2 or 3,each R individually is hydrogen, alkyl, cycloalkyl,aryl, aralkyl, alkoxy, cycloakoxy, aryloxy, hydroxyl,halogen, aminoalkyl or carboxyl,with the proviso thattwo R's together can represent the methylenedioxygroup or a fused-on, optionally heterocyclic andoptionally substituted ring,with oxygen or a gas containing molecular oxygen in aqueous alkaline medium in the presence of a catalyst comprising a platinum-group metal in the presence as an activator of at least one of lead, a lead compound, bismuth and a bismuth compound at a temperature of up to the boiling point of the resulting reaction mixture.
Abstract:
Preparations consisting of 5 to 90%, relative to the total weight of the preparations, of mainly neutralized 1-hydroxy-benzotriazole of the formula ##STR1## in which R.sup.1 and R.sup.2, independently of one another, represent hydrogen or methyl andM.sup..sym. is one equivalent of an alkali metal or alkaline earth metal cation or H.sup..sym., whereby M.sup..sym. is present in the range of 85-100 equivalent-% as alkali metal or alkaline earth metal cation and in the range of 15-0 equivalent-% as H.sup..sym.,and the remainder to 100% of water, whereby the water containing preparations have a pH value of from 3 to 11 are nonexplosive and can be handled without danger.For the preparation, unsubstituted 1-hydroxy-benzotriazole is neutralized with an aqueous solution or suspension of a hydroxide, bicarbonate or carbonate of an alkali metal or alkaline earth metal. These preparations may be present as solutions, suspensions or pastes.
Abstract:
N-aryl-N'-alkyl-piperazines are obtained in a particularly simple manner, in good yields and in short reaction times when an aniline is reacted under pressure with an N-alkyl-bishydroxyethyl-amine in the presence of a strong acid.
Abstract:
Process for the preparation of alkyl aryl ethers containing carboxyl groups which are suitable for the preparation of colour film couplers, or derivatives thereof, by reaction of aromatic alcohols with alkyl halides containing carboxyl groups or derivatives thereof and basic alkali metal or alkaline earth metal compounds, characterized in that the reaction is carried out in the melt of the aromatic alcohol.
Abstract:
4-Hydroxybiphenyl is obtained in non-thixotropic form if a reaction mixture which is obtained by alkaline hydrolysis of biphenyl-4-sulfonic acid and contains 4-hydroxybiphenyl is heated at elevated pressure at above 115.degree. C. and at a pH from 0 to below 6.5.
Abstract:
(2RS,3RS)-3-(2'-aminophenylthio)-2-hydroxy-3-(4"-methoxyphenyl)-propionic acid methyl ester, an important precursor for the preparation of the pharmaceutical active substance diltiazem, is obtained in a particularly high stereoselectivity and yield by addition of o-aminothiophenol onto 3-(4'-methoxyphenyl)-glycidic acid methyl ester if the reaction is carried out in the presence of alkali metal salts of weak acids in the presence of catalytic amounts of iron compounds.