摘要:
The present invention relates to a mixture comprising itaconic acid or an itaconic acid derivative and a primary amine of the formula (I) R—NH2 (I) where the molar ratio of primary amine to itaconic acid or the itaconic acid derivative is in the range from 0.5:1 to 20:1, wherein the mixture comprises 50 mole percent or less of 4-carboxypyrrolidones of the formula (II), derivatives of the 4-carboxypyrrolidones of the formula (II) and 4-carbamidopyrrolidones of the formula (III) based on the itaconic acid used or the itaconic acid derivative used and in which R is a linear or branched saturated aliphatic radical having 1 to 24 carbon atoms or a saturated cycloaliphatic radical having 3 to 24 carbon atoms.The invention further provides for the use of the inventive mixtures for preparing 1,3-alkylmethylpyrrolidones and/or 1,4-alkylmethylpyrrolidones, and also a process for preparing 1,3-alkylmethylpyrrolidones and/or 1,4-alkylmethylpyrrolidones.In addition, the present invention relates to mixtures comprising 1,3-alkylmethylpyrrolidones and/or 1,4-alkylmethylpyrrolidones and 1,3-alkylmethylpyrrolidines, where the proportion of 1,3-alkylmethylpyrrolidines is in the range from 10 to 10 000 ppm, and to mixtures comprising 1,3-alkylmethylpyrrolidone and 1,4-alkylmethylpyrrolidone, wherein the molar ratio of 1,3-alkylmethylpyrrolidone to 1,4-alkylmethylpyrrolidone is in the range from 1:1 to 10:1.
摘要:
The present invention relates to a process for preparing a compound II or a composition comprising the compound II to a composition comprising succinimide and to a composition prepared by the process according to the invention.
摘要:
The present invention provides a process for preparing lactones from optionally substituted, saturated aliphatic diols having from five to 20 carbon atoms between the two ring-closing hydroxyl groups by catalytic dehydrogenation and cyclization in the liquid phase over at least one catalyst.
摘要:
A process for preparing cyclododecanone by reacting cyclododecene with dinitrogen monoxide, comprising in particular steps (I) and (II): (I) preparing cyclododecene by partially hydrogenating cyclododecatriene; (II) reacting cyclododecene obtained in (I) with dinitrogen monoxide to obtain cyclododecanone.
摘要:
A process for preparing an N-alkyllactam with improved color quality, wherein from 0.01 to 10% by weight of a C1-10-alcohol or a compound which releases from 0.01 to 10% by weight of a C1-10-alcohol is added to the N-alkyllactam.A mixture comprising at least 99.0% by weight of an N-alkyllactam and in the range from 100 to 5000 ppm by weight of a C1-10-alcohol or of an acetal, aminal or of an Orthoester which releases in the range from 100 to 5000 ppm by weight of a C1-10-alcohol.
摘要:
The present invention provides a process for changing the given mean molecular weight Mn in the continuous preparation of polytetrahydrofuran or tetrahydrofuran copolymers, the mono- or diesters of polytetrahydrofuran or of tetrahydrofuran copolymers by polymerizing tetrahydrofuran in the presence of a telogen and/or of a comonomer over an acidic catalyst, wherein a) the molar ratio of telogen to tetrahydrofuran or to tetrahydrofuran and comonomer is changed, b) then the mean molecular weight of at least one sample is determined, c) until the mean molecular weight thus determined differs from the molecular weight to be achieved by the change, the already formed polytetrahydrofuran or the tetrahydrofuran copolymers, the mono- or diesters of polytetrahydrofuran or tetrahydrofuran copolymer is at least partly depolymerized over an acidic catalyst and d) the tetrahydrofuran recovered by depolymerization is recycled at least partly into the polymerization.
摘要:
The present invention relates to a process for preparing a compound II or a composition comprising the compound II to a composition comprising succinimide and to a composition prepared by the process according to the invention
摘要:
The present invention provides an integrated process for continuously preparing 1,4-butanediol, which comprises the following stages:(I) reacting formaldehyde with acetylene in the presence of a copper catalyst at a pH of from 5 to 8 and a molar ratio of formaldehyde to acetylene of at most 2:1, (II) intermediately buffering the resulting butynediol-containing aqueous mixture for from 0.1 to 100 h, (III) hydrogenating the mixture obtained after the intermediate buffering and (IV) distilling the hydrogenation product obtained in stage III to obtain 1,4-butanediol.
摘要:
The present invention relates to a solid, acid catalyst for the preparation of polytetrahydrofuran, polytetrahydrofuran copolymers, diesters or monoesters of these polymers by polymerization of tetrahydrofuran in the presence of at least one telogen and/or comonomer, which has a BET surface area of at least 160 m2/g and an acid center density of at least 0.05 mmol/g for pKa values of from 1 to 6, to a process for preparing it and to a process for the polymerization of cyclic ethers over this catalyst.
摘要:
A process for preparing cyclododecanone by reacting cyclododecene with dinitrogen monoxide, comprising in particular steps (I) and (II): (I) preparing cyclododecene by partially hydrogenating cyclododecatriene; (II) reacting cyclododecene obtained in (I) with dinitrogen monoxide to obtain cyclododecanone.