摘要:
The present invention relates to a 1,3-bis-(N-lactamyl)propane of general formula (I), wherein radicals R1, R2, R3, R4, R5 and R6 independently stand for hydrogen, alkyl, cycloalkyl, aryl or aralkyl and at least one of said radicals does not stand for hydrogen, (NLac) and (NLac′) are the same or different and stand for N-lactamyl radicals. The invention also relates to the use of said substances as a solvent in pharmaceutical and cosmetic agents. Disclosed are novel compounds of formula (I), wherein R1 and methyl and R2-R6 stand for hydrogen.
摘要:
Process for the treatment of wastewater from an aldolization process which is contaminated with water-soluble and/or dispersed organic impurities by means of single-stage or multistage extraction with an organic liquid of the aldolization process wastewater which has been set to a pH of from 0 to 6, in which an organic liquid obtained by stripping of the acidified aldolization process wastewater or of the acidified and extracted aldolization process wastewater, condensation of the stripped compounds and phase separation of the condensate is used as extractant for the extraction of organic impurities from the acidified aldolization process wastewater and wastewater having a lower content of organic impurities than the aldolization process wastewater fed to the extraction is taken off from the stripping apparatus.
摘要:
A process is disclosed for preparing D,L-aspartic acid by beating aqueous solutions of ammonium salts of the maleic acid. The molar ratio of maleic acid to ammonia ranges from 1:1 to 1:50. The process is carried out at temperatures from 60.degree. to 250.degree. C. and pressures of at least 1 bar. The pressure applied during the reaction is adjusted to ensure that the reaction mixture is almost completely present in liquid phase. Excess ammonia is removed and the reaction solution is acidified so as to release D,L-aspartic acid, which is then isolated.
摘要:
The use of hexahydrophthalimide compounds of the formula (I) is described as plasticizers for molding compositions, in particular polyvinyl chloride, in which R is alkyl, cycloalkyl, or cycloalkylalkyl, where the two last named moieties can be unsubstituted or alkyl-substituted, and the moiety R has at least 6 carbon atoms.
摘要:
A process for preparing 1,3-diols having 6 or more carbon atoms comprises a) provision of at least one alkanal having at least three carbon atoms; b) thermal treatment of the alkanal in the absence of a basic catalyst; c) hydrogenation of the aldol addition product formed in step b); and d) isolation of the 1,3-diol obtained. The process of the present invention makes it possible to prepare 1,3-diols simply and inexpensively.
摘要:
Alcohols are prepared by the catalytic hydrogenation of the corresponding carbonyl compounds at elevated temperatures and at superatmospheric pressure in the liquid phase by a process in which the catalyst used contains copper on an SiO2-containing carrier in the presence or absence of one or more of the elements magnesium, barium, zinc and chromium.
摘要:
A process is provided for increasing the yield in the preparation of polyhydric alcohols obtained from methylolated alkanals by hydrogenation, wherein derivatives of these alcohols are decomposed by adding 5 ppm to 1% by weight, preferably 100 to 1000 ppm, of a suitable acid to an anhydrous mixture containing these derivatives, heating the mixture to temperatures of 100 to 300° C. and then separating off the polyhydric alcohol by distillation. This process makes it possible simply and efficiently to decompose compounds which boil above the polyhydric alcohol and are unwanted by-products of its synthesis.
摘要:
A process for dehydrogenating 1,4-butanediol to .gamma.-butyrolactone in the gas phase in the presence of a copper-containing catalyst, wherein the catalyst contains 4-40% by weight of copper and 0-5% by weight of Na.sub.2 O, based on the total weight of the catalyst, on a carrier consisting of 80-100% by weight of SiO.sub.2 and 0-20% by weight of CaO.
摘要:
A process for the preparation of polyalcohols comprises the stages:(a) Reaction of an alkanal or ketone with formaldehyde in aqueous solution in the presence of a tertiary amine, to form a formates containing polyalcohol product mixture,(b) removal of water, excess tertiary amine, excess formaldehyde(c) heating of remaining mixture from (b) with removal of further formaldehyde and tertiary amine with formation of the formates of the polyalcohol,(d) transfer of tertiary amine removed from stage (b) and/or from stage (c), to synthesis stage (a) and/or to the subsequent transesterification stage (e),(e) transesterification of the resulting formates of the polyalcohol from stage (c) with an alcohol of the formula ROH in the presence of a transesterification catalyst to give polyalcohols and formates of the formula ##STR1## where R is a hydrocarbon radical, preferably alkyl of 1-6, particularly preferably 1-2, carbon atoms, and(f) isolation of the polyalcohols.
摘要:
1,6-Hexanediol is prepared bya) Reacting epoxybutadiene in the presence of a metathesis catalyst with elimination of ethene to give bisepoxyhexatrienes of the formulae Ia and Ib ##STR1## and b) hydrogenating these bisepoxyhexatrienes with hydrogen to give 1,6-hexanediol.