Rhenium heptoxide, a known catalyst for hydrogenation of carboxylic acids to alcohols, forms synergistic combinations with palladium, platinum, rhodium and ruthenium catalysts. This effect is also seen at lower presures (500 psi). Synergism is also mainfest when rhenium and palladium (or rhodium) are used as supported catalysts on silica and used in a flow mode. An interaction of unknown nature between the metals suggests itself. The process is not very efficient at lower pressures giving lower conversion in the flow mode. At higher temperatures needed for higher rates, significant participation of side reactions such as decarboxylation of the acid and hydrogenolysis of the alcohol occurs yielding hydrocarbons.
ABSTRACTBetulinol esters were prepared from stearic-, lauric-, palmitic-, oleic-and tall oil fatty acids via the acid-chloride and direct condensation routes. The degree of esterification was determined by high pressure liquid chromatography (HPLC), infrared (IR) and acid value measurements. The use of esters for air-dried, polyurethane and plastisol coatings was evaluated.
Some representative examples of a new family of aminimide monomers, i.e., trialkylamine N‐acryloyl or N‐methacryloyl glycinimides and β‐aminopropanimides have been prepared and studied. These are the first examples of a possible large family of primary aminimide monomers. With radical initiators, the acryloyl and monosubstituted methacryloyl monomers readily homopolymerize. The disubstituted methacryloyl aminimides do not homopolymerize under the same conditions. All of the new monomers copolymerize with styrene, methyl methacrylate, and n‐butyl acrylate. The various polymers were characterized by IR, DTA, TGA, GPC and inherent viscosities. When heated (160°C) the polymers liberate amine and crosslink in the presence of active hydrogen moieties to give resins with carbamate, urea, allophonate, etc., residues. When no active hydrogens are available during heating, polymers can be prepared with pendent primary isocyanate groups. This preliminary work shows these monomers to be highly useful for preparing a wide variety of reactive copolymers.
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