Abstract:
To provide a method capable of easily and efficiently removing a 2-alkoxyethanol from a mixture containing the 2-alkoxyethanol and a (2-alkoxyethyl) vinyl ether while suppressing a decrease in the yield of (2-alkoxyethyl) vinyl ether.A method for removing a 2-alkoxyethanol, including the step of adding one or more azeotropic solvents selected from the group consisting of alkanes having 7 to 8 carbon atoms and cycloalkanes having 7 to 8 carbon atoms to a mixture containing the 2-alkoxyethanol represented by the following formula (1) R—O—CH2CH2OH (1) where R represents an alkyl group having 1 to 4 carbon atoms, and a (2-alkoxyethyl) vinyl ether represented by the following formula (2) R—O—CH2CH2O—CH═CH2 (2) where R has the same meaning as R in the formula (1), and subjecting the resulting mixture to azeotropic distillation.
Abstract:
The present invention relates to ethers of 1,2-, 1,3- and 1,4-bis(hydroxymethyl)cyclohexanes, to the preparation of such ethers and also to the use of such ethers as fragrances and as formulation auxiliaries in fragrance-comprising preparations.
Abstract:
A process for producing a high-purity vinyl ether, which comprises: a step of subjecting an alcohol represented by the general formula (1) R—O—H (1) to a vinyl ether formation reaction in the presence of a catalyst to synthesize a vinyl ether represented by the general formula (2), R—O—CH═CH2 (2) a step of removing the catalyst from the reaction mixture obtained in the above step to obtain a crude vinyl ether containing the vinyl ether and the unreacted raw material alcohol, a step of reacting the unreacted raw material alcohol in the crude vinyl ether, with the vinyl ether in the presence of an acid catalyst, to convert the alcohol into an acetal represented by the general formula (3), and a step of subjecting a crude vinyl ether containing the acetal (III) to distillation to obtain a high-purity vinyl ether.
Abstract:
Alkenyl ethers are prepared by reacting the corresponding alcohols or phenols with acetylenes in the liquid phase in the presence of basic alkali metal compounds and a cocatalyst comprising compounds of the formula (Ia) and/or (Ib)R1Onull(CH2CH2CH2CH2O)nnullHnullnull(Ia)R1Onull(CH2CH2CH2CH2O)nnullH2,nullnull(Ia)where R1, R2 are, independently of one another, C1-C6-alkyl or C2-C6-alkenyl, or R1 and R2 together form a butyl unit and n is 1, 2, 3, 4 or 5.
Abstract:
Enol ethers of the formula (I) where R1 to R3 are each, independently of one another, hydrogen or a carbon-containing organic radical and R4 is an unsubstituted or substituted alkyl radical, are prepared by reacting alcohols of the formula (II) R4—OH (II), with alkynes of the formula (IlIa), alkadienes of the formula (IIIb) R1—C≡C—CHR2R3 (IIIa), R1—CH═C═CR2R3 (IIIb) or mixtures thereof, where R1 to R4 are as defined above, in the presence of an alkali metal alkoxide and a polar, aprotic solvent.
Abstract:
Process for carrying out gas/liquid reactions at from (-50.degree.) to 300.degree. C. and from 0.1 to 100 bar by carrying out the reaction in the absence of a continuous gas phase, and, as a special case, a process for the batchwise reaction of acetylene in the liquid phase at from 0.degree. to 300.degree. C. and from 2 to 30 bar, in which acetylene is introduced a) in the absence of a continuous gas phase and b) under isobaric conditions to a degree of saturation of from 5 to 100%.
Abstract:
The preparation of monovinyl ethers of the general formula I ##STR1## in which A stands for a chemical bond or for a methylene or ethylene group, the radicals R.sup.1 and R.sup.2 independently stand for hydrogen, alkyl, cycloalkyl, or aryl groups or R.sup.1 and R.sup.2 together form a C.sub.3 -C.sub.5 alkylene bridging member, by the reaction of a diol of the general formula II ##STR2## in which the variables have the above meanings, with acetylene in the presence of a base, in which the reaction is carried out at 150.degree.-250.degree. C. under an acetylene partial pressure of 5-25 bar until 40-80% of the diol has been converted, at which point the reaction is stopped and the monovinyl ether of the formula I is isolated.
Abstract:
The invention relates to a vinyloxy hydroxyalkyl cycloalkylene having the formulaHO(CH.sub.2).sub.x --A--(CH.sub.2).sub.x, OCH.dbd.CH.sub.2wherein x has a value of from 1 to 10; x' has a value of from 0 to 10 and A is a cycloalkylene group having from 3 to 8 carbon atoms in the ring and is optionally substituted with lower alkyl. The invention also relates to the method for synthesizing the above compounds.
Abstract:
The present invention relates to ethers of 1,2-, 1,3- and 1,4-bis(hydroxymethyl)cyclohexanes, to the preparation of such ethers and also to the use of such ethers as fragrances and as formulation auxiliaries in fragrance-comprising preparations.
Abstract:
A novel Rh(I)-catalyzed approach to synthesizing functionalized (E,Z) dienal compounds has been developed via tandem transformation where a stereoselective hydrogen transfer follows a propargyl Claisen rearrangement. Z-Stereochemistry of the first double bond suggests the involvement of a six-membered cyclic intermediate whereas the E-stereochemistry of the second double bond stems from the subsequent protodemetallation step giving an (E,Z)-dienal. The reaction may be represented by the following sequence.