Abstract: Pentenoic esters are prepared by heating formylvaleric esters at from 50.degree. to 400.degree. C. in the presence of zeolites or one or more phosphates selected from the group consisting of aluminum phosphate, silicon aluminum phosphate, boron aluminum phosphate, silicon iron aluminum phosphate, cerium phosphate, zirconium phosphate, boron phosphate, iron phosphate and strontium phosphate.

Abstract: Unsaturated ketones of the formula ##STR1## and saturated ketones of the formula ##STR2## where R.sup.1, R.sup.2 and R.sup.3 are each hydrogen, alkyl of 1 to 12 carbon atoms or a cycloalkyl, aryl, aralkyl or alkylaryl radical which inturn may be substituted, or R.sup.1 and R.sup.3 or R.sup.2 and R.sup.3, together with the carbon atoms to which they are bonded, may form a cycloalkane, are prepared by a process in which a 5-methylene-1,3-dioxolanone which is substituted in the 4-position and is of the forumla ##STR3## where R.sup.1, R.sup.2 and R.sup.3 have the above meanings, (a) for the preparation of an unsaturated ketone, is converted in the presence of a zeolite, of a phosphate having a zeolite structure and/or of B, Ce, Fe, Zr or Sr phosphate as catalysts and (b) for the preparation of a saturated ketone, is converted in the presence of the same catalysts which additionally carry one or more hydrogenation components.

Abstract: Pentasil coated catalysts and fully crystalline catalysts in which the individual pentasil crystals are larger than 5 .mu.m are prepared by hydrothermal treatment of SiO.sub.2 by a process in which the SiO.sub.2 moldings are subjected to a hydrothermal treatment at from 140.degree. to 220.degree. C. in an alkali-free mixture of water, an amine and/or a tetraalkylammonium compound, with or without ammonia. The aluminum component for the preparation of an aluminosilicate zeolite can be kneaded into the SiO.sub.2 moldings or fed in via the liquid phase during the hydrothermal treatment. The tetraalkylammonium compound used can be a tetra-n-propyl-ammonium salt or hydroxide.

Abstract: Ketones of the formula ##STR1## where R.sup.1 to R.sup.3 are each hydrogen and R.sup.1 to R.sup.4 are each alkyl of 1 to 12 carbon atoms, cycloalkyl of 4 to 8 carbon atoms, aryl, aralkyl or alkylaryl, which each in turn may be substituted, or R.sup.1 and R.sup.2 and R.sup.3 together with the carbon atoms to which they are bonded form a cycloalkane, are prepared by reacting ketones of the formula ##STR2## where one of R.sup.1, R.sup.2, R.sup.3 and R.sup.5 is hydroxyl, alkoxy or carboxyl while the remaining R.sup.1 to R.sup.4 have the abovementioned meanings, with hydrogen in the presence of acid catalysts supporting one or more hydrogenation components, zeolites of the pentasil type being particularly suitable.

Abstract: A novel fixed-bed catalyst structure obtained using honeycomb elements, for highly exothermic and endothermic chemical reactions, wherein the required heat exchange, both in the liquid phase and in the gas phase, is forcibly effected in the fixed catalyst bed by means of static mixing elements made of inert ceramic and/or metallic material or completely of catalyst material, between the individual honeycomb elements.

Abstract: 3-pentenoates are prepared from 2-pentenoates by a process in which(a) a 2-pentenoate of the formula ##STR1## where R.sup.1 is alkyl of 1 to 12 carbon atoms, cycloalkyl of 5 to 8 carbon atoms, aralkyl of 7 to 10 carbon atoms or aryl of 6 to 10 carbon atoms, is reacted with a compound of the formula IIR.sup.2 -X-H IIwhere R.sup.2 has the meanings given for R.sup.1 and X is an oxygen or sulfur atom, or with a compound of the formula III ##STR2## where R.sup.3 is hydrogen or R.sup.3 and R.sup.4 are each alkyl of 1 to 12 carbon atoms, cycloakkyl of 5 to 8 carbon atoms, aralkyl of 7 to 10 carbon atoms or aryl of 6 to 10 carbon atoms, and R.sup.3 and R.sup.4 together with the nitrogen atom on which they are substituents may form a 5-membered to 7-membered ring which may additionally contain a nitrogen or oxygen atom as a hetero atom, at from 20.degree. to 300.degree. C., in the presence or absence of a basic catalyst, to give a compound of the formula IV ##STR3## where Y is --XR.sup.2 or ##STR4## in which X, R.sup.

Abstract: 4-Formyltetrahydropyrans of the general formula I ##STR1## where R.sup.1 is hydrogen, C.sub.1 -C.sub.12 -alkyl, C.sub.2 -C.sub.12 -alkenyl, C.sub.1 -C.sub.6 -alkoxy-substituted C.sub.1 -C.sub.12 -alkyl, C.sub.4 -C.sub.12 -cycloalkyl, unsubstituted or substituted aryl, hetaryl or aralkyl, or an unsubstituted or substituted, saturated or unsaturated 5-membered or 6-membered ring which may be interrupted by N, O or S, are prepared by a process in which a pyran derivative of the general formula II ##STR2## where R.sup.1 is as defined above, R.sup.2 and R.sup.3 are each OH or together are an oxygen atom and thus form an oxirane ring, and R.sup.4 is hydrogen where R.sup.2 and R.sup.3 are each OH, and is hydrogen or tert-butoxycarbonyl where R.sup.2 and R.sup.3 together are an oxygen atom, is treated at elevated temperatures with a catalyst selected from the group consisting of zeolites, phosphates, boric acid on a carrier and silica or mixtures of these. Novel 4-formyltetrahydropyrans are also proposed.

Abstract: Cyclopentanone is prepared from adipic esters by reacting adipic esters of the formulaR.sup.1 OOC--(CH.sub.2).sub.4 --COOR.sup.2where R.sup.1 and R.sup.2 are alkyl of 1 to 12 carbon atoms, cycloalkyl of 5 or 6 carbon atoms, aralkyl or aryl and R.sup.2 can additionally be hydrogen, in the gas or liquid phase at from 150.degree. C. to 450.degree. C. in the presence of zeolitic catalysts and/or phosphate catalysts, preferably zeolites of the pentasil type.

Abstract: Bifunctional compounds of the formula ##STR1## where R.sup.1, R.sup.2 and R.sup.3 are each alkyl of 1 to 6 carbon atoms, R.sup.2 and R.sup.3 may furthermore be hydrogen, R.sup.2 is furthermore alkoxy and R.sup.4 is hydrogen, alkyl of 1 to 6 carbon atoms or alkoxy, and a double bond may be present between carbon atoms 2 and 3, are prepared by converting a tetraalkoxyalkane or a dialkoxyalkanoate of the formulae ##STR2## where R.sup.1, R.sup.2, R.sup.3 and R.sup.4 have the above meanings, in the presence of a catalyst, such as a zeolite, in particular one of the pentasil type, and/or a phosphate and/or phosphoric acid on a carrier.

Abstract: 1,4-Diacyloxybut-2-enes and 3,4-diacyloxybut-1-enes are converted into one another in the gas phase or liquid phase at from 100.degree. to 350.degree. C. under atmospheric or superatmospheric pressure in the presence of a zeolite as a catalyst.

Abstract: 1,4-Diazabicyclo[2.2.2]octane and C-substituted 1,4-diazabicyclo[2.2.2]octanes of the formula (I) ##STR1## where R.sup.1 and R.sup.2 are each hydrogen or alkyl or alkenyl, each of 1 to 4 carbon atoms, are prepared from a heterocyclic amine of the formula (II) ##STR2## where R.sup.1 and R.sup.2 have the above meanings, R.sup.3 is hydrogen, hydroxyethyl or aminoethyl and X is hydroxyl or amino, in the presence of borosilicate and/or iron silicate zeolites as catalysts. Particularly suitable catalysts are the borosilicate and iron silicate zeolites of the pentasil type.

Abstract: 4-Pentenoates are prepared by isomerization by a process in which isomeric pentenoates are treated with a zeolite of the pentasil type at from 50.degree. to 300.degree. C., and the 4-pentenoate is distilled off from the reaction mixture.

Abstract: But-2-enes are obtained from C.sub.4 -hydrocarbon mixtures which contain but-1-ene and may or may not contain but-2-enes by catalytic isomerization of the but-1-ene to but-2-enes in an isomerization zone at elevated temperatures by a process in which the isomerization is carried out in combination with a distillative separation zone, the said hydrocarbon mixture being fed to the isomerization zone and/or distillative separation zone, the isomerization mixture obtained from the isomerization zone is passed into the distillative separation zone, a but-1-ene-containing fraction is removed above the lower third of the distillative separation zone and passed into the isomerization zone, and the but-2-enes or a fraction containing these are or is removed in the lower third of the distillative separation zone.

Abstract: 4-Pentenoates are prepared by isomerization by a process in which isomeric pentenoates are treated at elevated temperatures in the presence of a zeolite containing metals of group eight of the Periodic Table and the 4-pentenoate is distilled off from the reaction mixture, and the zeolite contains iron, cobalt and/or nickel.

Abstract: Aliphatic dinitriles are prepared by reacting aliphatic dicarboxylic acids with ammonia in excess at from 200.degree. to 500.degree. C. in the presence of zeolites as catalysts.

Abstract: A honeycomb catalyst consisting of from 30 to 95% by weight, calculated as Fe.sub.2 O.sub.3, of an iron compound and from 0.1 to 60% by weight, calculated as Al.sub.2 O.sub.3, CeO.sub.2 or Cr.sub.2 O.sub.3, of an aluminum, cerium and/or chromium compound and/or from 1 to 50% by weight of an alkali metal compound, in particular potassium, calculated as K.sub.2 O, and/or from 0.2 to 20% by weight, calculated as MeO.sub.3, of an element of sub-group 6, preferably MoO.sub.3 and WO.sub.3, and/or from 0.1 to 20% by weight, calculated as V.sub.2 O.sub.5, of a compound of vanadium and/or from 0.1 to 20% by weight, calculated as P.sub.2 O.sub.5, of a compound of phosphorus, a process for the preparation of the honeycomb catalyst, and the use of the catalyst for organic reactions.

Abstract: 4-oxa-aldehydes are prepared by catalytic isomerization of a 1,3-dioxane using an acidic zeolite catalyst.

Abstract: Ketones are prepared by isomerization of aldehydes at elevated temperatures over zeolites.

Abstract: Alkylbenzenes are prepared by converting an alkyl-, alkylidene- or alkenylcyclohexene or an alkyl- or alkenylcyclohexadiene in the presence of an acidic zeolite catalyst of the pentasil type, in the gas phase or liquid phase.

Abstract: Olefins are prepared by converting methanol and/or dimethyl ether in the presence of a zeolite catalyst at elevated temperatures by a process wherein the catalyst used is a borosilicate zeolite which has been molded together with an amorphous binder containing aluminum oxide and silicon dioxide. The advantage of using the borosilicate catalyst is that the yield of C.sub.2 -C.sub.4 -olefins is improved at the expense of formation of higher hydrocarbons.