6044-68-4Relevant articles and documents
Process for producing a carboxylic acid ester by reacting an aldehyde and an alcohol using a palladium type catalyst
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Page column 4; 7-10, (2008/06/13)
A carboxylic acid ester is prepared by a process comprising: reacting an aldehyde and an alcohol in a liquid phase in the presence of molecular oxygen as indicated by the following reaction: RCHO+R′OH+O2→RCOOR′+H2O in the presence of a catalyst comprising at least palladium and an element X, wherein X is bismuth, lead or a combination thereof, supported on a carrier, wherein the catalyst has an acid strength, pKa, of more than 4.8 and shows an ammonia chemical adsorption amount at 0° C. of 0-150 μmol/g-catalyst.
Process and apparatus for producing alpha, beta-unsaturated acetals
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, (2008/06/13)
In a process for preparing α,β-unsaturated acetals by reacting an α,β-unsaturated aldehyde with a lower alcohol in the presence of a solid catalyst in a reaction vessel, the improvement comprising introducing a reaction product leaving the reaction vessel into a distillation column at a a stage between the topmost stage to the stage located just above the lowermost stage in the distillation column, and recycling a distillate from the distillation column to the reaction vessel.
INDIRECT ELECTROCHEMICAL α-METHOXYLATION OF ALIPHATIC ETHERS AND ACETALS - REACTIVITY AND REGIOSELECTIVITY OF THE ANODIC OXIDATION USING TRIS(2,4-DIBROMOPHENYL)AMINE AS REDOX CATALYST
Ginzel, Klaus-Dieter,Steckhan, Eberhard,Degner, Dieter
, p. 5797 - 5806 (2007/10/02)
The technically important α-methoxylation of aliphatic ethers and acetals to form mixed acetals respectively aldehydes or ortho-esters can be performed electrochemically at low potentials in methanol solution using an undivided cell and tris(2,4-dibromophenyl)amine as redox catalyst.The regioselectivity is usually considerably higher as compared with direct electrolysis in the abscence of a catalyst.Especially valuable is the method for the regioselective methoxylation of secondary carbon atoms in presence of primary or tertiary ones and of the acetal carbon in 1,3-dioxolanes.The redox catalyst is stable under the reaction conditions so that more than thousand turnovers could be obtained.
Photo- and thermal isomerization of some 1-methoxyallyl cations
Childs, Ronald F.,Hagar, Mark E.
, p. 1788 - 1794 (2007/10/02)
The 1-methoxy-, 1-methoxy-3-methyl-, and 1-methoxy-2,3-dimethylallyl cations, 2, 5, and 9, were prepared by treatment of the dimethyl acetals of acrolein, crotonaldehyde, and tiglaldehyde, respectively, with FSO3H.Each of these ions was capable of existing in various stereoisomeric forms.The thermodynamically preferred conformation of 2, 5, and 9 all had a C1-O, E configuration and 5 and 9 an E configuration about the C2-C3 bonds.Irradiation of FSO3H solutions of these ions at -70 deg C using 254 nm light caused them to be converted to the other stereoisomers.Relatively efficient photoisomerism about both the C1-O and C2-C3 bonds was observed.The rates of the reverse thermal conversion of the photoproducts to 2, 5, and 9 were measured and on the basis of medium and substituent effects it was concluded that thermal isomerism about the C1-O bond takes place by an inversion process while stereomutation about the C2-C3 bond involves the addition of base to C3.
