Abstract: A process for the continuous synthesis of dialkyl carbonates of the general formula I ##STR1## in which R denotes C.sub.1 -C.sub.4 -alkyl, by reaction of C.sub.1 -C.sub.

Abstract: A process for the acylation of an alkyl aromatic hydrocarbon with a derivative of carboxylic acid by the Friedel-Crafts method in the presence of a Friedel-Crafts catalyst and an organo-aluminum compound, wherein the organo-aluminum compound is an alumoxane.

Abstract: A process for the preparation of vinyl phosphonic derivatives of the general formula I ##STR1## in which R.sup.1 and R.sup.2 are the same or different and may stand for hydrogen or a C.sub.1 -C.sub.8 -alkyl, a C.sub.6 -C.sub.10 -aryl, or a C.sub.8 -C.sub.10 -aralkyl radical optionally substituted by Cl or Br, and in which R.sup.1 and R.sup.2 may alternatively be joined together to form an alicyclic ring having from 3 to 12 carbon atoms in the ring, wherein an ethane phosphonic ester of the general formula II ##STR2## in which R.sup.3 and R.sup.4 have the meanings stated above for R.sup.1 and R.sup.2 except for hydrogen and X denotes a hydroxy group, a halogen atom, or a radical of the formula--OR.sup.5,in which R.sup.5 is a hydrogen atom or a radical of the formula ##STR3## in which R.sup.6 is a C.sub.1 -C.sub.6 -alkyl radical or an alicyclic ring, is converted in the gas phase in the presence of a solid catalyst.

Abstract: A process for the preparation of amines of the formula ##STR1## in which R.sup.1 is the radical H.sub.2 N-CH.sub.2 and R.sup.2 is hydrogen, or R.sup.1 and R.sup.2 together form a bridging group --CH.sub.2 --, by reacting 1,3,6-tricyanohexane at elevated temperature and pressure with hydrogen in contact with a catalyst containing, in addition to cobalt oxide, and oxide of an alkali metal, an oxide of an alkaline earth metal, an oxide of a rare earth or an oxide of scandium or yttrium.

Abstract: Polytetrahydrofuran derivatives of the general formula ##STR1## where n is from 2 to 70, X is the bridge member --NH-- or --O-- and R.sup.1 and R.sup.4 are each hydrogen or various radicals.

Abstract: A process is described for isolating tetrahydrofuran from mixtures containing tetrahydrofuran, 1,4-butanediol, -butyrolactone and succinic acid esters, in which the mixtures are heated to from 150.degree. to 250.degree. C. in the presence of phyllosilicates, the resultant tetrahydrofuran and water of reaction are removed from the reaction mixture by distillation, and the tetrahydrofuran is separated from the distillate.

Abstract: Polytetrahydrofuran ethers of the formulaR.sup.1 --O--(CH.sub.2).sub.4 ].sub.n O--R.sup.2 Iwhere n is a number from 3 to 70, and R.sup.1 and R.sup.2 are hydrocarbon radicals containing 3 to 5 carbon atoms and a double bond, but where R.sup.2 may alternatively be hydrogen.

Abstract: A process is described for the preparation of propylene glycol and ethylene glycol from formaldehyde, the first step involving conversion of the formaldehyde into a mixture of polyhydroxyl compounds in a conventional manner in an alkaline medium by self-condensation and the second step involving catalytic hydrogenolysis of this mixture with a hydrogen consumption of at least 0.5 mol of hydrogen per mol of formaldehyde employed for forming the polyhydroxyl compounds.

Abstract: 2-Hydroxy-4-(2'-hydroxyethoxy)phenyl aryl ketones I ##STR1## where Ar is substituted or unsubstituted aryl, are prepared by reacting 2,4-dihydroxyphenyl aryl ketones II ##STR2## with ethylene carbonate in the presence of an alkali metal or alkaline earth metal salt of a carboxylic acid as catalyst and purified with sodium dithionite.

Abstract: Cyclopentenones of the formula I ##STR1## where each of R.sup.1 to R.sup.4 is independently of the others hydrogen or an organic radical, are prepared by converting a carboxylic ester of the formula IIa, IIb or IIcR.sup.1 CH.dbd.CR.sup.2 --CHR.sup.3 --CHR.sup.4 --CO.sub.2 R.sup.5 (IIa) and/orR.sup.1 CH.sub.2 --CR.sup.2 .dbd.CR.sup.3 --CHR.sup.4 --CO.sub.2 R.sup.5(IIb) and/orR.sup.1 CH.sub.2 --CHR.sup.2 --CR.sup.3 .dbd.CR.sup.4 --CO.sub.2 R.sup.5(IIc),where each of R.sup.1 to R.sup.4 is as defined above and R.sup.5 is C.sub.1 -C.sub.8 -alkyl, over an acidic heterogeneous catalyst at 50.degree.-800.degree. C. and 0.001-50 bar.

Abstract: A process is described for the preparation of high purity polymers or copolymers obtained by cationic polymerization of tetrahydrofuran and, if desired, alkylene oxide, in which hydrogen having a bubble diameter of less than 50 .mu.m is passed into the polymers in the presence of a hydrogenation catalyst.

Abstract: The preparation of 1-hydroxyimidazoles of the formula I ##STR1## where the R radicals can be identical or different and are each halogen or an organic radical, it also being possible for vicinal radicals to be connected to form an aromatic or nonaromatic ring of from 3 to 12 carbon atoms, and n is from 0 to 3, entails reacting an imidazole of the formula II ##STR2## where Q is preferably hydrogen or, especially where R is not halogen, an alkali metal or alkaline earth metal cation, with an organic peroxide.The products are valuable intermediates for organic syntheses.

Abstract: N-Aryl-substituted 2-amino-alkyl-2-hydroxyalkylamines and N-aryl-substituted piperazines Ia and Ib respectively ##STR1## (Ar=aryl; R.sup.1 =hydrogen, methyl, identical or different, R.sup.2 =hydrogen, alkyl) are prepared by reacting an N,N-di(2-hydroxyalkyl)-N-arylamine II ##STR2## with ammonia or a primary amine IIIH.sub.2 N-R.sup.2 IIIat elevated temperature and under elevated pressure in the presence of hydrogen and of a catalyst which is a supported catalyst whose active mass predominantly contains copper and/or nickel and/or cobalt in the form of the metal or an oxide.

Abstract: The preparation of 2-formyl-2-methyl succinates by reacting itaconates with carbon monoxide and hydrogen in contact with a catalyst system comprising rhodium and a tertiary phosphorus compound, wherein the reaction is carried out under a pressure of from 90 to 325 bar.

Abstract: Transition metal complexes of the general formula I[A].sup.x- [Q].sup.+ x Iwhere Q is one equivalent of a cation, x is from 0 to 2 and A is a transition metal complex of the general formula ##STR1## where n is from 1 to 3, M is positively charged cobalt, rhodium, iridium or ruthenium, the ligands B are phosphonic, arsonic, phosphinic and/or arsinic acid ligands which are esterified with identical or different alcohols, one or more of these alcohol components carrying a functional group, L is ##STR2## the radicals R.sup.5 are identical or different radicals from the group consisting of C.sub.1 -C.sub.4 -alkyl and phenyl, p is an integer from 0 to 6, q is an integer from 0 to 5, and R.sup.1 is fluorine, chlorine, bromine, iodine, cyanide, isocyanide, cyanate, isocyanate, thiocyanate, isothiocyanate, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.

Abstract: A process for the preparation of N-substituted pyrrolidin-2-ones of the general formula I ##STR1## where R.sup.1 is C.sub.1 - to C.sub.20 -alkyl, C.sub.6 - to C.sub.10 aryl or C.sub.7 - to C.sub.12 -aralkyl comprises hydrogenolytically cleaving 5-iminopyrrolidin-2-ones of the general formula II ##STR2## in which the R.sup.1 radicals are identical or different C.sub.1 - to C.sub.20 -alkyl, C.sub.6 - to C.sub.10 -aryl or C.sub.7 - to C.sub.12 -aralkyl, at super-atmospheric pressure and elevated temperature in the presence of a hydrogenation catalyst to give the pyrrolidin-2-ones I; specifically, the 5-iminopyrrolidin-2-ones of the formula II are obtained by reacting .beta.-cyanopropionic acid esters of the general formula III ##STR3## where R.sup.2 is C.sub.1 - to C.sub.20 -alkyl, C.sub.7 - to C.sub.12 -aralkyl or C.sub.6 - to C.sub.10 -aryl, with an amine of the general formula IVR.sup.1 --NH.sub.2 IVwhere R.sup.1 is as defined above.

Abstract: A process for the preparation of polyether glycols by polymerization of tetrahydrofuran or copolymerization of tetrahydrofuran with oxiranes in the presence of from 20 to 500% w/w of a hydrocarbon, based on the weight of tetrahydrofuran used.

Abstract: A process is described for the purification of crude polyalkylene ether glycols contaminated by heteropolyacids or salts thereof, by treatment with solvents, which comprises mixing the crude polyalkylene ether glycols with a liquid hydrocarbon and water, allowing the phases to separate, and isolating the purified polyalkylene ether glycols from the upper phase.

Abstract: A process for the preparation of bis(4-chlorophenyl) sulfone, wherein sulfur trioxide, dimethyl sulfate and chlorobenzene are reacted with each in a single reaction at a temperature of from 50.degree. to 100.degree. C.

Abstract: The invention relates to novel alkoxy substituted maleimides of the formula ##STR1## where R.sup.1 is hydrogen, C.sub.1 -C.sub.8 -alkyl, C.sub.2 -C.sub.8 -alkenyl, phenyl or phenylalkyl, and the organic radicals may furthermore carry inert substituents, and R.sup.2 and R.sup.3 are each C.sub.1 -C.sub.4 -alkyl, C.sub.2 -C.sub.4 -alkenyl, C.sub.1 -C.sub.4 -haloalkyl or C.sub.2 -C.sub.4 -haloalkenyl, and alkoxy-substituted maleic anhydrides of the formula II ##STR2## where R.sup.2 is C.sub.1 -C.sub.4 -alkyl, C.sub.2 -C.sub.4 -alkenyl, C.sub.1 -C.sub.4 -haloalkyl or C.sub.2 -C.sub.4 -haloalkenyl and Z is hydrogen, halogen or a radical OR.sup.3, where R.sup.3 is C.sub.1 -C.sub.4 -alkyl, C.sub.2 -C.sub.4 -alkenyl, C.sub.1 -C.sub.4 -haloalkyl or C.sub.2 -C.sub.4 -haloalkenyl.The invention further relates to processes for preparing such maleimides I and the corresponding maleic anhydrides II and their use as graft monomers in graft polymers based on polyphenylene ethers.