Stamicarbon B.v.

Holland Sweetener Company V.o.v.

Hubertus J Delahaye

Antonius J Teunissen

Cornelis G Van De Moesdijk

Willem Klop

Johan Thomas Tinge

Theodorus F De Graaf

Theodorus J Van De Mond

Adelbert A Drinkenburg

The invention relates to a process for the preparation of an oligopeptide or amino acid alkyl ester.HCl salt, the alkyl group being methyl, ethyl, isopropyl or n-propyl, by converting an oligopeptide.HCl salt or amino acid.HCl salt with an alkanol corresponding to the alkyl group under the influence of an acid catalyst, 0.01-0.5 mol HCl relative to the oligopeptide.HCl salt or amino acid.HCl salt in combination with an acid ion exchange resin being used as acid catalyst.

Preparation of oligopeptide or amino acid alkyl ester.HCl salts

The invention relates to a process for preparing a 2-alkyl-1,4,5,6-tetrahydropyrimidine with the formula ##STR1## where R represents a straight or branched chain with 1-8 C-atoms or a phenyl group from 1,3-diaminopropane and an alkanecarboxylic acid, in which the alkyl group of such an acid is the same as the R group described above, wherein the starting materials are reacted in the gas phase in the presence of an oxide catalyst at a temperature of between 250.degree. and 450.degree. C. and from the reaction mixture thus obtained the 2-alkyl-1,4,5,6-tetrahydropyrimidine is recovered.

Process for preparing a 2-alkyl-1,4,5,6-tetrahydropyrimidine

The invention provides a process for the preparation of pyrimidine, 2-methyl- and/or 2-ethylpyrimidine, characterized in that for pyrimidine a nitrogen reactant, chosen from the reaction product of formamide with 1,3-diaminopropane in the liquid phase, 1-amino-3-formamidopropane, 1,4,5,6-tetrahydropyrimidine and/or 1,3-diformamidopropane, that for 2-methylpyrimidine 1-amino-3-acetamidopropane, 2-methyl-1,4,5,6-tetrahydropyrimidine and/or 1,3-diacetamidopropane, and that for 2-ethylpyrimidine 1-amino-3-propionamidopropane, 2-ethyl-1,4,5,6-tetrahydropyrimidine and/or 1,3-dipropionamidopropane is/are contacted with a palladium-containing catalyst, this being effected in the gas phase at a temperature between 200.degree. and 550.degree. C. and in the presence of a carbon monoxide-hydrogen reactant, and that pyrimidine, 2-methyl-and/or 2-ethyl-pyrimidine is recovered from the reaction mixture obtained.

Process for the preparation of pyrimidine and 2-alkylpyrimidine

The process according to the invention for the preparation of a 2-propyl- or 2-butylpyrimidine, in which the corresponding 2-alkyl-1,4,5,6-tetrahydropyrimidine is dehydrogenated in the gas phase with a palladium-containing catalyst and in which a 2-propyl- or 2-butylpyrimidine is recovered from the reaction mixture, is characterized in that the gas-phase reaction is carried out using a carbon monoxide-hydrogen reactant. As this is understood a mixture of carbon monoxide and hydrogen and/or a compound capable of at least partial decomposing into CO and H.sub.2 under the reaction conditions.

Process for the preparation of a 2-alkylpyrimidine

An improved process for the dehydrogenation of alcohols, to produce aldehydes therefrom, using a copper-containing catalyst, is described wherein the alcohol is introduced in the gas phase initially in admixture with an inert gas only, and after an initial reaction period the alcohol is continued to be introduced, in the gas phase, in an admixture with an inert gas together with a minor amount of hydrogen. As a result, prolonged catalyst activity with retained selectivity is achieved.

Method for the preparation of aldehydes

An improved process for the preparation of cyclohexanone from benzene. Benzene is hydrogenated in a gaseous phase in a hydrogenation zone to form cyclohexane; cyclohexane is oxidized in a liquid phase to form a mixture containing cyclohexanol and cyclohexanone; and cyclohexanone is separated from this mixture and is catalytically dehydrogenated to form cyclohexanone and a hydrogen containing gas. The resulting hydrogen containing gas is introduced into a washing zone wherein it is washed with cyclohexane or benzene and the hydrogen gas thus purified is fed into the hydrogenation zone.

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Voerendaal, Netherlands

Hubertus J Delahaye