Abstract: .alpha.-Alkylacroleins are prepared by reacting an alkanal with formaldehyde and a secondary amine in the presence of a carboxylic, dicarboxylic or polycarboxylic acid in certain molar ratios within a pH range of from 2.5 to 7 and at from 0.degree. to 150.degree. C.The .alpha.-alkylacroleins which can be prepared by the process described are valuable starting materials for dyes, drugs and pest control agents.
Abstract: A process for the preparation of 2-methylene aldehydes is disclosed wherein formaldehyde is reacted with an aldehyde of the general formula R--CH.sub.2 CHO, where R stands for a substituted or unsubstituted organic radical having from 2 to 12 carbon atoms. The reaction takes place in the presence of a mixture of a secondary amine and an organic carboxylic acid having up to 5 carbon atoms.
Type:
Grant
Filed:
December 29, 1980
Date of Patent:
August 24, 1982
Assignee:
Ruhrchemie AG
Inventors:
Hanswilhelm Bach, Eike Brundin, Wilhelm Gick
Abstract: A process for the preparation of 2-methyl-2-sec.butyl-1,3-propanediol comprising hydroformylating 2-methyl-1-butene with carbon monoxide and hydrogen in the presence of a first catalyst to form the substance 3-methyl-pentanal, condensing said substance with formaldehyde, or a compound which forms formaldehyde under the conditions of condensation in a basic medium to form alpha-sec.butyl-acrolein, partially hydrogenating said acrolein in the presence of a second catalyst to form the material 2,3-dimethyl pentanal, and converting said material into said diol by treatment with formaldehyde, or a compound which forms formaldehyde under the conditions of conversion, in the presence of a strong base as a third catalyst.The compound of the present invention is useful as an intermediate in the production of pharmaceuticals and drugs; in particular, the production of carbamates which are useful as tranquilizers and blood pressure lowering agents.
Type:
Grant
Filed:
August 15, 1980
Date of Patent:
March 2, 1982
Assignee:
Ruhrchemie Aktiengesellschaft
Inventors:
Wolfgang Bernhagen, Jurgen Weber, Helmut Bahrmann, Helmut Springer
Abstract: In the present invention aliphatic aldehydes are condensed to form .alpha.,.beta.-unsaturated aldehydes by use of a heterogeneous catalyst. Such process uses an anatase titanium dioxide catalyst in a fixed bed process under mild temperature conditions to yield high conversions and high yields, and which also eliminates the catalyst removal steps required by conventional processes.
Abstract: A process for preparing methacrolein by catalytic reaction of propionaldehyde with formaldehyde is disclosed wherein the catalyst comprises a mixture of secondary amine and organic carboxylic acid with up to 8 carbon atoms.
Type:
Grant
Filed:
December 21, 1979
Date of Patent:
August 11, 1981
Assignee:
Ruhrchemie AG
Inventors:
Wolfgang Bernhagen, Hanswilhelm Bach, Eike Brundin, Wilhelm Gick, Helmut Springer, Adolf Hack
Abstract: Aldehydes or ketones of not less than 4 or 5 carbon atoms, respectively, are manufactured in a one stage process in the liquid phase by subjecting aldehydes and/or ketones of not less than 2 or 3 carbon atoms, respectively, to an aldol condensation and hydrogenating the resulting olefinically unsaturated aldehyde, the catalyst used for the aldol condensation and hydrogenation containing nickel or cobalt or their mixtures, zinc oxide and at least one of the elements iron, arsenic, antimony, bismuth, gallium, indium, thallium, germanium, tin, lead, cadmium and mercury or compounds of the said elements.
Type:
Grant
Filed:
February 12, 1979
Date of Patent:
December 16, 1980
Assignee:
BASF Aktiengesellschaft
Inventors:
Axel Nissen, Gerd Heiien, Ekkehard Sapper, Werner Fliege, Arnold Wittwer
Abstract: An improvement in a process for the preparation of 2,2-dimethylolalkanal of the formula ##STR1## where R denotes an optionally substituted aliphatic radical by reacting 2-alkylacrylaldehyde with formaldehyde in presence of water and a base, the improvement residing in employing an aldehyde of the formula ##STR2## wherein R has the meaning indicated above and a mol ratio of the same to formaldehyde of 1:8-30 at a temperature in the range from -10 to 100.degree. C.
Abstract: This invention relates to an improved method for the catalyzed condensation of aldehydes in the liquid phase to form 1,3-glycol monoesters utilizing tin metal or a tin oxide catalyst. Condensation can be visualized as an aldol condensation followed by a Tischenko reaction between the aldol and a third molecule of aldehyde. In its simplest form the condensation can be illustrated by the following general formula ##STR1## R or R.sup.1 =Hydrogen or alkyl group of 1 to 20 carbon atoms or aromatic groups. R and R.sup.1 can also be part of a cyclic system.
Abstract: A method of producing acrolein comprising evaporating acetaldehyde and formaldehyde in the presence of diphenyl-N-nitrosamine taken in an amount of from 0.1 to 3 wt. %. The resultant vapors of said aldehydes are fed for aldol condensation which occurs in a gaseous phase on a catalyst, viz., coarsely porous silica gel promoted by 10 to 12 wt. % sodium silicate at a temperature of from 270.degree. to 300.degree. C. in the presence of diphenyl-N-nitrosamine taken in a quantity of from 0.1 to 3 wt. %. The resultant gas mixture formed at the stage of aldol condensation, containing acrolein, acetaldehyde, formaldehyde and water is cooled to obtain a condensate. Said condensate is subjected to rectification in order to isolate a mixture of acrolein with acetaldehyde and water, and an aqueous formaldehyde solution. Said aqueous formaldehyde solution is concentrated and returned to the aforesaid evaporation stage.
Type:
Grant
Filed:
June 29, 1976
Date of Patent:
September 16, 1980
Inventors:
Boris N. Gorbunov, Alexandr P. Khardin, Alexandr I. Valdman, Vyacheslav K. Rykov, Stanislav V. Sukhanov
Abstract: This invention relates to mixtures, in the form of relatively low viscosity liquids at room temperature, of formose, aldehydes and/or ketones aldolated in the .alpha.-position and, optionally, water and/or crystalline mono- or di-saccharides, and to the use of these mixtures for the production of polyurethane plastics, particularly foams.
Abstract: Chemical control of aldol reactions has been achieved by employing a combination of inorganic base-cationic or neutral surfactant catalysts with organic carbonyl compounds.