摘要:
The invention relates to a process for obtaining a pure aliphatic dialdehyde monoacetal by reaction of the corresponding aliphatic dialdehyde or a precursor of the corresponding aliphatic dialdehyde with one or more aliphatic mono- or polyhydric alcohols while distillatively removing water to obtain a reaction mixture which is separated distillatively, which comprises carrying out the distillative separation continuously in a dividing wall column to obtain pure aliphatic dialdehyde monoacetal as a sidestream from the dividing wall column, or in two distillation columns to obtain crude aliphatic dialdehyde monoacetal as a sidestream in the first distillation column, feed the crude aliphatic dialdehyde monoacetal to the second distillation column and obtain pure aliphatic dialdehyde monoacetal as the sidestream from the second distillation column.
摘要:
A system comprising a) Ni(0) b) from 4 to 10 mol per mol of Ni(0) in a) of a compound (I) of the formula P(X1R1)(X2R2)(X3R3) (I) where X1, X2, X3 are each, independently of one another, oxygen or a single bond, R1, R2, R3 are, independently of one another, identical or different organic radicals and c) from 1 to 4 mol per mol of Ni(0) in a) of a compound (II) of the formula where X11, X12, X13 X21, X22, X23 are each, independently of one another, oxygen or a single bond, R11, R12 are identical or different, individual or bridged organic radicals, R21, R22 are identical or different, individual or bridged organic radicals and Y is a bridging group is suitable as catalyst for preparing mixtures of monoolefinic C5 mononitriles having nonconjugated C═C and C═N bonds by hydrocyanation of a 1,3-butadiene-containing hydrocarbon mixture and for preparing a dinitrile by hydrocyanation of a mixture of monoolefinic C5 mononitriles having nonconjugated C═C and C═N bonds.
摘要翻译:一种系统,其包含a)式(I)中的式(ⅰ)中的每一摩尔Ni(0)中的Ni(0)b)4至10摩尔的式(ⅰ)的线性式描述=“在线式” 结束=“铅”→P(X 1> 1 SUP>)(X 2 2 R 2)(X (I)<?in-line-formula description =“In-line Formulas”end =“tail”?>其中X <1> X 2,X 3,X 3各自彼此独立地为氧或单键,R 1,R 2, > 2,R 3彼此独立地为相同或不同的有机基团,c)1至4摩尔每摩尔a)化合物中的Ni(0) II),其中X 11,X 12,X 13,X 21,X 22 X 23,X 23各自彼此独立地为氧或单键,R 11,R 12和R 12相同或相同, 不同的单个或桥连的有机基团,R 21,R 22和R 22相同或不同,单个或桥接的有机基团和 Y是桥联基团,适合作为通过含1,3-丁二烯的烃混合物的氢氰化制备具有非共轭CC和CN键的单烯键式C 5 H 5单体的混合物的催化剂,并通过氢氰化制备二腈 的具有非共轭CC和CN键的单烯烃C 5 H 5单体的混合物。
摘要:
The present invention relates to a process for preparing trioxime derivatives of the formula I in which the substituents R1 and R2 are identical or different and each is cyano, alkyl, haloalkyl or cycloalkyl, and R3 and R4 are identical or different and each is alkyl, haloalkyl, cycloalkyl, alkylcarbonyl or arylalkyl, by the following reaction steps in water without isolation of the intermediates: A) nitrosation of 1,3-diketones of the formula II to give monooximes of the formula III, B) oximation of III with hydroxylamine derivatives of the formula IV H2N—OR3′ IV in which R3′ is hydrogen or a group R3 to give bisoximes of the formula V, C) alkylation of V with alkylating agents or acylation of V with acylating agents to give compounds of the formula VI and D) subsequent oximation of VI with hydroxylamine to give compounds of the formula I.
摘要:
Display with a heater, a) the display having at least one display glass, b) the heater having an electrically operated heating element connected to a voltage supply (UB, GND), c) the heating element comprising a thin layer, d) the layer being made of a material forming an electrical resistance, and e) the layer being applied over a surface area to the at least one display glass or being embedded over a surface area in the display. f) A first measuring instrument (4) is provided, which determines the resistance value of the heating element, g) a second measuring instrument (5) is provided, which determines the level of the voltage present at the heating element, h) a third measuring instrument (3) is provided, which senses the current ambient temperature at the display, i) a memory (7) is provided, which stores the determined resistance value of the heating element, j) a logic unit (6) is provided, which determines for the stored resistance value in accordance with the determined voltage and the determined ambient temperature a current-supplying period for the heating element necessary to produce that heat output which will heat up the display to a certain operating temperature within a predetermined time, and k) a switching element (8) actuated by the logic unit (6) is provided, which regulates the current flow through the heating element connected to the voltage supply (UB, GND) for the current-supplying period determined.
摘要:
Amines are prepared by reacting aldehydes or ketones at elevated temperature under elevated pressure with nitrogen compounds selected from the group of ammonia, primary and secondary amines, and with hydrogen in the presence of a catalyst containing copper, wherein the catalytically active mass of the catalyst contains, before the reduction with hydrogen, 20 to 85% by weight of oxygen-containing compounds of zirconium, calculated as ZrO2, 1 to 30% by weight of oxygen-containing compounds of copper, calculated as CuO, 14 to 70% by weight of oxygen-containing compounds of nickel, calculated as NiO, 0 to 5% by weight of oxygen-containing compounds of molybdenum, calculated as MoO3, and 0 to 10% by weight of oxygen-containing compounds of aluminum, calculated as Al2O3.
摘要翻译:胺在升高的温度下在升高的温度下与选自氨,伯胺和仲胺的氮化合物和氢气在含催化剂的聚合物的存在下反应制备,其中催化剂活性物质含有, 在用氢还原之前,以ZrO 2计为20〜85重量%的含氧化合物,以30重量%计,氧化铝为14〜70重量%,氧化铝为100重量% 以NiO表示的镍化合物,以MoO 3计为0〜5重量%的含氧化合物的钼和0〜10重量%的按Al 2 O 3计算的含氧化合物的铝。
摘要:
A catalyst comprising at least one nickel(0) complex which comprises at least one mono-, bi- or multidentate phosphonite ligand of the formula I or salts and mixtures thereof, is prepared as described, and the catalysts are used to prepare mixtures of monoolefinic C5 mononitriles with nonconjugated C═C and C≡N bonds by catalytic hydrocyanation of butadiene or of a 1,3-butadiene-containing hydrocarbon mixture in the presence of a catalyst of this type.
摘要:
A process is described for the continuous preparation of dimethylvinylcarbinol (DMVC) by continuously reacting prenol with the aqueous solution of a protic acid in the still or in the lower part of a rectification column while distilling off the DMVC formed in the form of an azeotropic mixture with water, which comprises a) during the reaction ensuring that as far as possible no liquid two-phase mixture forms in the reaction mixture, b) distilling off the DMVC which forms at a reflux ratio of at least 2, as a result of which there is virtually no more prenol present in the distillate from the column, and c) setting the reaction volume and/or the amount of prenol added per hour and/or the concentration of protons in the reaction mixture in such a manner that the quotient, defined as residence time concentration coefficient, of the reaction volume and the volume of prenol added per hour multiplied by the concentration of protons in the reaction mixture has a value between 0.001 h·mol/l and 1 h·mol/l. In this connection, the formation of a liquid two-phase mixture in the reaction mixture is prevented, in addition to avoiding too large a prenol excess, by continuously taking from the reaction mixture a partial stream, passing it over a phase separation vessel, completely or at least largely removing there the small quantities, formed in the course of the reaction, of organic by-products which are insoluble or only partially soluble in water, and returning the aqueous phase to the reaction volume.
摘要:
A process for preparing mixtures of monoolefinic C5 mononitriles with nonconjugated C═C and C≡N bonds by catalytic hydrocyanation of 1,3-butadiene or a 1,3-butadiene-containing hydrocarbon mixture, wherein the hydrocyanation takes place in the presence of a catalyst which comprises at least one metallocene-phosphorus(III)-nickel(0) complex which comprises at least one monodentate or bidentate metallocene-phosphorus(III) ligand of the formula I or salts and mixtures thereof.
摘要:
Optically active amines are racemized by reaction of the optically active amine in the gas phase at elevated temperature in the presence of hydrogen and a hydrogenation or dehydrogenation catalyst.
摘要:
In a process for racemizing optically active amines by reacting the optically active amine in the presence of hydrogen and a hydrogenation or dehydrogenation catalyst at elevated temperature, the reaction is carried out in liquid phase and the catalyst comprises the catalytically active constituents copper, silver, iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and/or platinum and a support material selected from the group consisting of aluminum oxide, zirconium dioxide, titanium dioxide, carbon and/or oxygen compounds of silicon.