摘要:
The invention relates to a method for producing macrocyclic ketones of general formula (I) by direct cyclisation of compounds of general formula (II) in the gas phase on a heterogeneous catalyst. In general formula (I), X represents a monounsaturated or polyunsaturated or saturated C10–C17 alkyl radical which can be optionally substituted by a C1–C6 alkyl radical, and in general formula (II), R1, R2 can respectively be the same or different and represent hydrogen or C1–C6 alkyl, and has the above-mentioned designation.
摘要:
The invention relates to a method for producing macrocyclic ketones of general formula (I) by direct cyclisation of compounds of general formula (II) in the gas phase on a heterogeneous catalyst. In general formula (I), X represents a monounsaturated or polyunsaturated or saturated C10-C17 alkyl radical which can be optionally substituted by a C1-C6 alkyl radical, and in general formula (II), R1, R2 can respectively be the same or different and represent hydrogen or C1-C6 alkyl, and has the above-mentioned designation.
摘要:
A process for preparing acetals of the formula I where a) the Rs are, independently of one another, a C1-C20-alkyl or C3-C20-alkenyl radical, or b) the two R radicals together form the members of an unsubstituted or C1-C10-alkyl-substituted 5- to 7-membered cyclic acetal, by reacting 3-methyl-2-butenal in the presence of sulfamic acid, of a N-(C1-C8-alkyl)sulfamic acid or of a N,N-di(C1-C8-alkyl)sulfamic acid as catalyst with: an alcohol of the formula R—OH (IIa), or an orthoester of the formula HC—(OR)3 (III) or a mixture of an alcohol of the formula (IIa) and an orthoester of the formula (III), or an alcohol of the formula HO—(CH2)m—OH (IIb), where m is a number from 2 to 4, and (CH2)m group in the alcohol IIb may be substituted by a C1-C10-alkyl group.
摘要:
A process for preparing substituted imidazoles of the formula I ##STR1## R.sup.1, R.sup.2 and R.sup.3 are identical or different and are each hydrogen, halogen, NO.sub.2, CN or a C.sub.1 -C.sub.20 -hydrocarbon radical which is unsubstituted or substituted by one or more halogens or R.sup.1 and R.sup.2 together are members of a 3- to 20-membered hydrocarbon ring which is unsubstituted or substituted by one or more halogens and/or C.sub.1 -C.sub.8 -alkyl groups and which may contain 1, 2 or 3 heteroatoms from the group consisting of nitrogen, oxygen and sulfur, andR.sup.4 is a C.sub.1 -C.sub.20 -hydrocarbon radical which is unsubstituted or substituted by one or more halogens,comprises using an aqueous phase of the imidazoles of the formula II ##STR2## where R.sup.1, R.sup.2 and R.sup.3 are as defined above with compounds of the formula IIIR.sup.4 --O--R.sup.5 IIIwhereR.sup.4 is as defined above andR.sup.5 is hydrogen or R.sup.4, it being possible in the latter case for the two R.sup.4 substituents to be identical or different,and reacting it at from 200.degree. to 550.degree. C. in the presence of a catalyst comprising oxides and/or phosphates of one or more metals of the 2nd, 3rd and 4th main group and the 4th subgroup of the Periodic Table in the presence or absence of phosphoric acid and/or phosphoric esters.
摘要:
A process for the preparation of imidazo[1,2-a]-5,6,7,8-tetra hydropyridin-8-ones by reaction of γ-butyrolactones with imidazols, novel imidazo[1,2-a]-5,6,7,8-tetrahydropyridin-8-ones, and their use for the preparation of imidazo[1,2-a]pyridines are described.
摘要:
Process for preparing homoallyl alcohols by catalyzed reaction of alkenes with aldehydes or ketones, wherein the reaction is carried out in the gas phase in the presence of noncovalently supported ionic liquid phase catalysts.
摘要:
Process for preparing 4-cyclohexyl-2-methyl-2-butanol The present invention relates to a process for preparing 4-cyclohexyl-2-methyl-2-butanol. The process comprises the following steps: a) reaction of styrene with isopropanol at elevated temperature to obtain 4-phenyl-2-methyl-2-butanol, and b) heterogeneously catalyzed hydrogenation of 4-phenyl-2-methyl-2-butanol over a catalyst suitable for ring hydrogenation of aromatics.
摘要:
The present invention relates to a process for preparing phenylalkan-1-ols in three stages, where an ester condensation in the presence of alkali metal or alkaline earth metal alcoholates is carried out in the first stage.
摘要:
The invention relates to a process for the preparation of m-substituted alkyltoluenes of the formula (I) in which R1 is C1-C5-alkyl, wherein a p-substituted alkyltoluene of the formula (II) in which R1 has the meaning given under formula (I), is isomerized in the presence of ionic liquids to give an m-substituted alkyltoluene of the formula (I). The m-substituted alkyltoluenes obtainable according to the invention are starting compounds for the preparation of fragrances and aroma substances.