Dsm N.v.

Stamicarbon B.v.

Anna M Castelijns

Richard Green

Henricus J Arts

Joannes M Mulders

Egbert Willem Meijer

Atze Jan Nijenhuis

Franciscus H Vandenbooren

Ellen M De Brabander-van Den Berg

Hubertus J Bosman

Christiaan J Stoelwinder

Hendrikus C De Man

Simon P Van Nispen

Johanna M Hogeweg

Hubertus J Dielemans

Rafael W Reintjens

Peter J Maas

Paulus L Alsters

Alie Kuiterman

Patrick H Delanghe

Thomas M Aarts

Cornelis W Van Den Broek

Dominique M Callant

The invention relates to a process for preparing .alpha.-amino acid amides, the corresponding .alpha.-amino acids, or salt thereof, which are substituted at the .beta.-site with at least one (hetero)aromatic group. This is achieved according to the invention by subjecting a 4-carbamoyl-2-oxazolidinone compound, respectively a 4-carboxy-2-oxazolidinone compound, wherein each of them is substituted at the 5-site with at least one (hetero)aromatic group, to a treatment with H.sub.2 in the presence of a catalyst. The invention also relates to a process for preparing a 4-carbamoyl-2-oxazolidinone compound substituted at the 5-site with at least one (hetero)aromatic group, in which process an .alpha.-amino-.beta.-hydroxy-propane nitrile substituted at the .beta.-site with at least one (hetero)aromatic group, or a salt thereof, is subjected to a treatment in the presence of CO.sub.2 and a base.

Process for preparing .alpha.-amino acid amides, .alpha.-amino acids and

Method for the preparation of N-alkoxy-(tetra- or hexahydro)-phthalimide according to formula I ##STR1## R.sub.1 being methyl or ethyl and R.sub.2 and R.sub.3 being each independently of one another hydrogen or alkyl with 1-4 C atoms or R.sub.2 and R.sub.3 together with the carbon atom to which they are bonded forming a ring with 5 or 6 C atoms, wherein the salt of the corresponding N-hydroxy-(tetrahydro- or hexahydro)-phthalimide according to formula II: ##STR2## with R.sub.2 and R.sub.3 as defined above and M being an alkali metal, is brought into contact with R.sub.1 Cl as alkylating agent, wherein R.sub.1 has the aforementioned meaning. The N-alkoxy-(tetra- or hexahydro)-phthalimide can afterwards be converted with the aid of hydroxylamine sulphate into the corresponding alkoxyamine after which the alkoxyamine obtained can be isolated. In this manner a simple and commercially attractive process for the preparation of O-(m)ethylhydroxylamine can be implemented.

Method for the preparation of a N-alkoxy-(tetra-or

Process for the preparation of 3-phenylpropanal in which cinnamaldehyde is hydrogenated with the aid of a Pd-containing catalyst in the presence of a small amount of water. A high yield and a high selectivity are obtained in a commercially attractive process. The reaction mixture obtained can without intermediate further processing be subjected to an oxidation in which the cinnamaldehyde is oxidized to 3-phenylpropionic acid with a high degree of conversion and a high selectivity. The combination of the two process steps constitutes a simple, commercially attractive process for the preparation of 3-phenylpropionic acid using cinnamaldehyde as a starting material. The resulting 3-phenyl-propionic acid product may serve as an intermediate reagent in the synthesis of anti-viral pharmaceuticals, particularly HIV protease inhibitors.

Process for the preparation of 3-phenylpropanal

Process for the preparation of 3-phenylpropionic acid in which 3-phenylpropanal is subjected to an oxidation, at elevated temperature, in particular at a temperature of between 40.degree. and 80.degree. C., using a medium containing molecular oxygen. A high degree of conversion and a high selectivity are obtained. The starting material 3-phenylpropanal can be prepared in a suitable manner through the hydrogenation of cinnamaldehyde in the presence of a Pd-containing catalyst, after which the reaction mixture obtained can without intermediate further processing be used in the oxidation reaction. The combination of the two process steps constitutes a simple, commercially attractive process for the preparation of 3-phenylpropionic acid using cinnamaldehyde as a starting material. 3-phenylpropionic acid can be used in particular in the preparation of pharmaceuticals such as HIV protease inhibitors.

Process for the preparation of 3-phenylpropionic acid

The invention relates to a method for preparing an .alpha.-alkylcinnamaldehyde via aldol concensation of a benzaldehyde and an alkanal, with pyrrolidine being employed as a catalyst. The method is suitable, in particular, for preparing .alpha.-hexylcinnamaldehyde by aldol condensation of benzaldehyde and n-octanal, in particular for preparing .alpha.-hexylcinnamaldehyde of olfactory quality, since it was found that, in the method according to the invention, relatively little .alpha.-hexyldecenal, the aldol condensation product of n-octanal, is formed. Preferably, the aldol condensation is carried out without a solvent in the presence of an acid, and the alkanal is metered in over time to a mixture which contains pyrrolidine and benzaldehyde.

Method for preparing an alpha-alkycinnamaldehyde

Process for the preparation of N-alkyl-N,O-diacetyl hydroxylamine, for instance N-methyl-N,O-diacetyl hydroxylamine, by catalytic reduction of a nitroalkane, for instance nitromethane, in the presence of acetic anhydride. As catalyst preferably a platinum on alumina catalyst is used. The invention provides a simple one-step process for the preparation of N-alkyl-N,O-diacetyl hydroxylamine in a relatively concentrated reaction medium.

Process for the preparation N-alkyl-N,O-diacetyl hydroxylamine

The present process involves preparing dibenzylamine through the hydrogenation of benzaldehyde in the presence of ammonia and a catalyst containing palladium using a small amount of solvent or dispersion medium. With the present process, dibenzylamine can be prepared with high selectivity in a relatively short reaction time and with complete conversion of the benzaldehyde, at which makes it commercially attractive. In the present process, a palladium-carbon catalyst is preferably used.

Process for the preparation of dibenzylamine

The invention relates to a dendritic macromolecule comprising a core and branches emanating from the core wherein the branches are based on vinyl cyanide and/or fumaryl dinatrile units. The invention also relates to processes for preparing these dendritic macromolecules. The dendritic macromolecules according to the invention are not sensitive to degradation through hydrolysis reactions and are also very stable at a high temperature. The processes are very suitable for large scale production of the dendritic macromolecules without requiring purification of reaction intermediates.

Dendritic macromolecule and the preparation thereof

Process for the preparation of substituted pyridines via

The invention relates to a process for the preparation of high yields of 5-oxohexane nitriles with minimum formation of 1 undesired isomer. Such nitriles may be utilized as starting materials for the preparation of pharmaceutical and agrochemical intermediates and as well as final products. The process comprises reacting a methyl ketone and an .alpha.,.beta.-unsaturated nitrile in the presence of a catalytically effective amount of a strong base. One of the products which may be created by the process is 2,4-dimethyl-5-oxohexane nitrile.

2,4-dimethyl-5-oxohexane and a method of use therefor

The invention relates to a method for the preparation of a 2-(2-cyanoethyl)-cyclopentanone by reaction of a cyclopentanone which contains at least one .alpha.-H atom with an .alpha.,.beta.-unsaturated nitrile in the presence of a catalytic amount of pyrrolidine as catalyst and optionally also a catalytic amount of an acid compound. A high selectivity and a high catalyst activity are achieved with the method.

Method for the preparation of 2-(2-cyanoethyl)-cyclopentanones

Process for the .alpha.-chlorination of phenylacetonitriles, for example benzyl cyanide, in which the phenylacetonitrile is contacted with a suitable chlorinating agent, sulphuryl chloride or chlorine gas, while an amount of strong acid, preferably HCl, is also present in the reaction mixture. The induction time and the reaction rate are dependent on, among other factors, the concentration of the acid. Preferably, the reaction is carried out under pressure. The reaction is well controllable.

Process for the .alpha.-chlorination of phenylacetonitriles

Process for the preparation of 5-oxohexane nitriles and the compound

The invention relates to a process for the preparation of 2-cyanomethylcyclohexanone by

Growing community of inventors

Beek, Netherlands

Anna M Castelijns