Abstract: The S-enantiomer of 3-chloro-1,2-propanediol is prepared by reaction of a chlorodeoxy-D-saccharide having the partial structure. ##STR1## to cleave the glycol, reduce the aldehyde so formed to an alcohol, and hydrolyse the alcohol under mild acidic conditions.
Abstract: This invention relates to an improved process for the preparation of a mixture of various low molecular weight hydroxyaldehydes, hydroxyketones and polyhydric alcohols by the condensation of formaldehyde with itself. The essential feature of the improvement is that unpurified synthesis gases of the kind obtained from the large scale industrial production of formaldehyde can be used directly as the source of formaldehyde.
Abstract: Disclosed is a process for the coupling of a Grignard reagent RMgX with an allylic halide in the presence of a dipolar aprotic solvent wherein the improvement, for obtaining improved yield and selectivity, comprises adding a catalyst to said Grignard or allylic halide and then carrying out the coupling reaction by the addition of the Grignard reagent to the allylic halide, said reaction being characterized by the displacement at the gamma position (relative to the halide) of the allylic halide with R of the Grignard reagent, migration of the allylic double bond in the direction of the halogen atom and loss of halogen. The present invention also resides in the discovery of certain novel procedures for the synthesis of Vitamin E. Specific embodiments of this aspect of the invention reside in the syntheses of 6,7-dehydrophytol, 10,11-dihydrofarnesene, phytone, hexahydropseudoionone, and related compounds as precursors for Vitamin E.
Abstract: Aliphatic carbonyl compounds are prepared by an aldol condensation of carbonyl compounds R.sup.1 --CH.sub.2 --CO--R.sup.2 (I; R.sup.1 and R.sup.2 =H or C.sub.1 -C.sub.8 -alkyl) in the presence of hydrogen and of a catalyst which has both condensing and hydrogenating properties, by using a catalyst system wherein the active components are from 1 to 90 percent by weight of a noble metal of group VIII of the periodic table and from 10 to 99 percent by weight of an oxide or salt of a rare earth metal, or of a mixture of different oxides and/or salts of rare earth metals.
Abstract: A process is disclosed for preparing mixtures of low molecular weight polyhydroxyl compounds and hydroxyaldehydes and hydroxyketones by condensing formaldehyde hydrate with itself in the presence of (I) as catalyst a soluble or insoluble compound of a metal of the first to eighth sub-group or second to fourth main group of the Periodic System of Elements, optionally bound to a high molecular weight carrier, and (II) more than 10% by weight, based on formaldehyde, of one or more dihydric or higher hydric low molecular weight alcohols and/or higher molecular weight polyhydroxyl compounds. The pH of the reaction mixture is held at 5.5 to 9.0 until 5-40% conversion has occurred and is then lowered to between 4.5 and 8.0 (0.5-2.0 pH units lower). The reaction is then stopped by inactivating the catalyst.
Abstract: Disclosed is a process for the coupling of a Grignard reagent RMgX with an allylic halide in the presence of a dipolar aprotic solvent wherein the improvement, for obtaining improved yield and selectivity, comprises adding a catalyst to said Grignard or allylic halide and then carrying out the coupling reaction by the addition of the Grignard reagent to the allylic halide, said reaction being characterized by the displacement at the gamma position (relative to the halide) of the allylic halide with R of the Grignard reagent, migration of the allylic double bond in the direction of the halogen atom and loss of halogen. The present invention also resides in the discovery of certain novel procedures for the synthesis of Vitamin E. Specific embodiments of this aspect of the invention reside in the syntheses of 6,7-dehydrophytol, 10,11-dihydrofarnesene, phytone, hexahydropseudoionone, and related compounds as precursors for Vitamin E.
Abstract: Disclosed are improved procedures for preparing pinacolone from compounds of general formula (I) ##STR1## wherein, either adjacent two of A, B, C and D form a single bond between them and the remaining two are hydrogen atoms, or both A and D are hydrogen atoms and one of B and C is a hydrogen atom and the other represents OH, Cl, Br, HSO.sub.4, H.sub.2 PO.sub.4 or ClO.sub.4, anda new procedure which enables preparing pinacolone from a compound of general formula (II) ##STR2## wherein, both W and Y are each hydrogen atoms and X and Z are the same or different and each represents OH, Cl, Br, HSO.sub.4, H.sub.2 PO.sub.4, ClO.sub.4 or RCOO wherein R is a hydrogen atom or an alkyl group of 1 to 3 carbon atoms, or one of W and Y is a hydrogen atom and the other forms a single bond together with X, and Z represents OH, Cl, Br, HSO.sub.4 H.sub.2 PO.sub.4, ClO.sub.4 or RCOO where R is defined as above.
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: This invention relates to an improved process for the preparation of a mixture of various low molecular weight hydroxyaldehydes, hydroxyketones and polyhydric alcohols by the condensation of formaldehyde with itself. The essential feature of the improvement is that unpurified synthesis gases of the kind obtained from the large scale industrial production of formaldehyde can be used directly as the source of formaldehyde.
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.