Ciba-geigy Corporation

Novartis Finance Corporation

Heinz Steiner

Gottfried Seifert

Peter Baumeister

Dieter Reinehr

Guido Bold

Hans-Georg Capraro

Hans Tobler

Rudolf Maul

Alexander Fassler

Helmut Prestel

Wolfgang J Tritschler

The invention relates to a novel process for the preparation of compounds of formula I ##STR1## wherein R.sub.1 is hydrogen or a suitable amino-protecting group,

Intermediates for the preparation of peptide analogues

A process for the preparation of substituted benzenes or benzenesulfonic acid and its derivatives comprising diazotisation of an aminobenzene or ortho-amino-benzenesulfonic acid derivative followed by homogeneous palladium-catalyzed coupling with an olefine and heterogeneous palladium-catalyzed hydrogenation of the olefinic substituent, wherein the homogeneous catalyst is reduced and precipitated as metal after the coupling in the reaction mixture and used as a heterogeneous palladium catalyst for the hydrogenation step. The process is particular suitable for the preparation N-benzenesulfon-N'-triazinyl-urea herbicides.

Process for the preparation of substituted benzenes and benzene sulfonic

A process for the preparation of substituted benzenes or benzenesulfonic acid and its derivatives comprising diazotisation of an aminobenzene or ortho-amino-benzenesulfonic acid derivative followed by homogeneous palladium-catalysed coupling with an olefine and heterogeneous palladium-catalysed hydrogenation of the olefinic substituent, wherein the homogeneous catalyst is reduced and precipitated as metal after the coupling in the reaction mixture and used as a heterogeneous palladium catalyst for the hydrogenation step. The process is particular suitable for the preparation N-benzenesulfon-N'-triazinyl-urea herbicides.

Process for the preparation of N,N'-substituted ureas

A process for the preparation of compounds of formula I ##STR1## wherein R.sub.1 and R.sub.2 are each independently of the other hydrogen, C.sub.1 -C.sub.12 alkyl, C.sub.5 -C.sub.6 cycloalkyl or phenyl, and R.sub.3 and R.sub.4 are each independently of the other C.sub.1 -C.sub.18 alkyl, C.sub.5 -C.sub.6 cycloalkyl, phenyl, phenyl which is substituted by C.sub.1 -C.sub.6 alkyl and/or hydroxy, or phenyl-C.sub.1 -C.sub.4 alkyl. The process comprises reacting a compound of formula III ##STR2## with a nitrite in aqueous or aqueous/organic medium to a compound of formula II ##STR3## extracting said compound of formula II from the reaction solution with a solvent, hydrogenating said compound, without isolation, in the cited solvent and in the presence of a palladium catalyst, to the corresponding p-aminophenol, and reacting said aminophenol, without isolation, with cyanuric chloride and a compound of formula HSR.sub.3 or HSR.sub.4 or a mixture of compounds of formulae HSR.sub.3 and HSR.sub.4. The products are obtained in high yield and purity.

Process for the preparation of alkylhydroxyanilinothiotriazine

Dihalobutyraldehydes of formula I ##STR1## wherein X and Y are each independently of the other Cl or Br, are obtainable at high rates of conversion and with excellent selectivities by catalytic dehalogenation with hydrogen by carrying out the reaction with appropriate .alpha.,.alpha.-dihalobutyraldehydes in an organic aprotic solvent. The dihalobutyraldehydes are intermediates for the synthesis of herbicidal acyl cyclohexanediones.

Process for the preparation of dihalobutyraldehydes

The preparation of 4,4'-stilbenedialdehydes from the corresponding acid chlorides in the presence of a noble metal catalyst.

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Munchenstein, Switzerland

Heinz Steiner