摘要:
Compounds of the formula I and II ##STR1## where R.sup.1 is hydrogen or an aliphatic, cycloaliphatic, araliphatic, aromatic or heterocyclic radical or an acyl radical, it being possible for these radicals to carry further substituents which do not react with acetylenes or allenes, and the radicals R, independently of one another, are hydrogen or aliphatic, cycloaliphatic, araliphatic, aromatic or heterocyclic radicals which may be linked to one another with formation of a ring and m is 0 or 1, are prepared by an addition reaction of a compound of the formula IIIR.sup.1 OH IIIwith an acetylene or allene of the formula IV or V ##STR2## where R.sup.1 and R have the abovementioned meanings, in the gas phase at elevated temperatures in the presence of a heterogeneous, silicate-containing catalyst, by a process in which the catalyst used contains, as an active component, an X-ray amorphous zinc silicate or cadmium silicate containing from 1 to 40% by weight, calculated as oxide, of zinc or cadmium and is obtainable by applying a zinc salt or cadmium salt of an organic acidic compound which is decomposable at below 400.degree. C., to an amorphous silica and forming the catalyst at from 50 to 500.degree. C., in the presence of a hydroxyl-containing compound selected from the group consisting of water, alkanols with up to 10 carbon atoms, diols and polyols having 2 to 6 carbon atoms and 2 or 3 OH groups and carboxylic acids of 1 to 6 carbon atoms.
摘要翻译:式I和II的化合物,其中R 1是氢或脂族,脂环族,芳脂族,芳族或杂环基或酰基,这些基团可能携带另外不与炔或炔反应的取代基和基团 R 2彼此独立地是氢或脂族,脂环族,芳脂族,芳族或杂环基团,其可以通过形成环而彼此连接并且m为0或1,其通过将化合物 式IIIR1OHIII具有式IV或V的乙炔或二烯,其中R1和R具有上述含义,在气相中,在非均相含硅酸盐催化剂存在下,在升高的温度下,通过所用催化剂包含的方法, 作为活性成分,含有以氧化物计为1〜40重量%的锌或镉的X射线无定形硅酸锌或铯硅酸盐,可通过应用 在低于400℃下可分解的有机酸性化合物的锌锌盐或镉盐加入到无定形二氧化硅中,并在50-500℃下,在含羟基化合物存在下,在选自 具有至多10个碳原子的链烷醇,具有2至6个碳原子的二醇和多元醇以及2或3个OH基团以及1至6个碳原子的羧酸组成的组。
摘要:
A process is described for preparing N-substituted 3-hydroxypyrazoles of the formula I ##STR1## where R.sup.1 is unsubstituted or substituted alkyl, alkenyl, alkynyl, cycloalkyl, aryl or heteroaryl andR.sup.2, R.sup.3 are hydrogen, cyano, halogen and unsubstituted or substituted alkyl, alkenyl, alkynyl, cycloalkyl, aryl or heteroaryl,by oxidizing a corresponding pyrazolidin-3-one.
摘要:
Preparation of epoxides from olefins by means of aromatic peroxycarboxylic acids comprises a step A of epoxidizing the olefin and removing the resulting aromatic carboxylic acid from the epoxide, a step B of catalytically hydrogenating the removed aromatic carboxylic acid to the corresponding aromatic aldehyde, and a step C of oxidizing this aldehyde with oxygen or an oxygen-containing gas mixture back to the aromatic peroxycarboxylic acid for re-use for epoxidizing an olefin.
摘要:
The invention relates to a process for the oxidation of mesitol with singlet oxygen, which is released from hydrogen peroxide, this release taking place in the presence of a bismuth compound as catalyst. In the process, 2,4,6-trimethylquinol is formed in high yield and selectivity as product, which can be used in further reactions for the synthesis of vitamins and in particular of vitamin A and vitamin E.
摘要:
The present invention relates to a process for carrying out a chemical reaction in the presence of a ruthenium-carbene complex supported on silicon dioxide in a continuously operated reactor and also the use of corresponding supported catalysts in continuously operated reactors.
摘要:
The present invention relates to a process for preparing at least one cyclic compound with Z cycles and 7 to 16 carbon atoms with a keto group, at least comprising the stages: (a1) oxidation of a composition (A), at least comprising one cyclic olefin with Z cycles and 7 to 16 carbon atoms and at least two C—C double bonds, by means of dinitrogen monoxide to give a composition (A1), (a2) separating off the at least one cyclic olefin with Z cycles and 7 to 16 carbon atoms with at least two C—C double bonds from the composition (A1) in order to obtain a composition (A2), and (b) distillative treatment of the composition (A2) from step (a2) in order to obtain a composition (B), comprising the at least one cyclic compound with Z cycles and 7 to 16 carbon atoms with a keto group and less than 1.0% by weight of the at least one compound with Z−1 cycles and 7 to 16 carbon atoms with at least one aldehyde group, where Z can be 1, 2, 3 or 4.
摘要:
A process for the preparation of 2-oxo-[1,3] dioxolane-4-carboxylic acid esters of formula I with R being an organic group comprising 1 to 10 carbon atoms, wherein an oxirane-2-carboxylic acid ester of formula II is reacted with carbon dioxide (CO2) at a pressure of at least 35 bars and a temperature of 60 to 80° C.
摘要:
Ketones of the formula II where A is optionally alkyl-substituted C2-C12-alkanediyl, R1 and R2 are each, independently of one another, C1-C6-alkyl, or R1 and R2 together form optionally alkyl-substituted C3-C10-alkanediyl, and R3 is hydrogen or C1-C6-alkyl, are prepared by reacting a cyclic olefin of the formula I with dinitrogen monoxide to form the ketone of the formula II. The ketone of the formula II can be further hydrogenated to form the saturated ketone of the formula III. Macrocyclic ketones of the formula III, e.g. muscone, are sought after as fragrances.
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 cyclopentanone, at least comprising the following steps (i) to (iii): (i) providing a mixture G(i) comprising cyclopentene; (ii) providing liquid or supercritical N2O or a liquid or supercritical gas mixture G(ii) comprising at least 20% by volume of N2O, based on the total volume of the mixture G(ii); (iii) contacting the mixture G(i) with the liquid or supercritical N2O or the liquid or supercritical mixture G(ii) to obtain a mixture G(iii) comprising cyclopentanone, wherein the mixture G(i) contains at least 25% by weight and at most 95% by weight, of cyclopentene, based on the total weight of the mixture G(i).