Hoechst Aktiengesellschaft

Erhard Jagers

Heinz Erpenbach

Andreas Seidel

Klaus Gehrmann

Reinhard Gradl

Wilhelm Vogt

Hermann Glaser

Georg Kohl

Norbert Weferling

Peter Heymanns

Peter Prinz

Manfred Bohshar

Peter Horstermann

Hanss-Jerg Kleiner

Alfred Hauser

Hans-Peter Koll

Karen Pottkamper

Hermann Berwe

In a process for preparing methyltris(m-sulfonatophenyl)phosphonium iodide trisodium salt, the sodium salt of trisulfonated triphenylphosphine and methanol are introduced as the initial charge, a solution of methyl iodide in methanol is added dropwise at elevated temperature, and after an additional reaction time the reaction product is evaporated to dryness in vacuo. Methyltris(m-sulfonatophenyl)phosphonium iodide trisodium salt can be used to prepare carboxylic acids and/or their esters by carbonylation of saturated aliphatic alcohols having from 1 to 20 carbon atoms or their halo, ester or ether derivatives over a rhodium catalyst in the presence of water and methyl iodide under a CO partial pressure of from 0.3 to 200 bar at a temperature of from 100.degree. to 240.degree. C., provided methyltris(m-sulfonatophenyl)phosphonium iodide trisodium salt and carboxylic acid are added to the liquid phase prior to carbonylation.

Preparation of methyltris(m-sulfonatophenyl) phosphonium iodide

To prepare acetic acid and acetic anhydride, methanol and methyl acetate are reacted under anhydrous conditions with carbon monoxide in the presence of a catalyst system containing carbonyl complexes of group VIII noble metals, methyl iodide, an alkali metal acetate or iodide, or quaternary organophosphonium or organoammonium acetate or iodide, The hot carbonylation mixture is decompressed, the evaporated components are fed to a first distillation zone, and the catalyst solution which remains is fed back to the reaction zone. In the first distillation zone, the volatile carbonylation products are subjected to fractional distillation; the low-boiling methyl iodide and methyl acetate pass back into the reaction zone, and the bottom product produced is a mixture of acetic acid and acetic anhydride, which is split into the pure components in a second distillation zone and a third distillation zone.

Process for the preparation of acetic acid and acetic anhydride

In a process for the stabilization of a solution of ethylmagnesium carbonate in ethanol, which has been prepared by the reaction of a suspension of magnesium ethylate in ethanol with carbon dioxide, 0.2 to 1.0% by weight of water, based on the ethylmagnesium carbonate solution, is added to the solution or its starting materials.

Process for the stabilization of ethanolic ethylmagnesium carbonate

Waste acetic acid, which is contaminated by nitrogen compounds and also by hardly hydrolyzable halogen compounds, is purified by adding a complex-forming metal or one of the compounds thereof and a basic compound. The resultant mixture is kept at a temperature between 25.degree. and 118.degree. C. over a period of time of 1 to 6 hours. Finally, purified acetic acid is removed from the mixture by distilling.

Process for the purification of waste acetic acid

A process for inhibiting and destroying peroxides in dialkyl ethers having the general formula R.sub.1 OR.sub.2 in which R.sub.1 and R.sub.2 are alkyl groups having 1 to 6 carbon atoms, which comprises adding, as inhibitor, a quaternary alkyl iodide of the general formula

Process for inhibiting and destroying peroxides in dialkyl ethers

A process for removing metallic corrosion products from carbonylation reactions which are carried out under anhydrous conditions and in which methyl acetate and/or methanol and/or dimethyl ether are reacted over a noble metal catalyst system which comprises a noble metal of group VIII of the periodic table of the elements, a co-catalyst, such as iodide or bromide, in particular methyl iodide, and a promoter, such as an organophosphonium or organoammonium salt, and if appropriate a lithium salt, to give acetic acid and/or acetic anhydride is described, the process comprising

Process for removing metallic corrosion products from carbonylation

In order to prepare N-acylphosphinothricin diesters, acetals of methyl-(3-oxopropyl)phosphinic acid esters of the formula ##STR1## are reacted in a dipolar aprotic solvent with a carboxylic acid amide and carbon monoxide in the presence of hydrogen gas using a cobalt compound as a catalyst, where the radical R' is alkyl or aryl or aralkyl.

Process for the preparation of N-acylphosphinothricin diesters

In order to prepare phenylalanine n-propyl ester hydrochloride, phenylalanine hydrochloride is reacted with n-propanol in the molar ration 1: (5 to 20) at temperatures from 80.degree. to 110.degree. C., preferably 85.degree. to 105.degree. C., at pressures from 0.1 to 1.5 bar in the presence of 0.1 to 0.75 mole of HCl/mole of phenylalanine hydrochloride as catalyst and in the presence of water entrainer, a concentration of water entrainer of 20 to 50% by weight being maintained in the reaction mixture.

Process for the preparation of phenylalanine n-propyl ester hydrochloride

The disclosure relates to a process for making acetic anhydride by reacting methyl acetate and/or dimethylether with carbon monoxide, which may be used in admixture with up to 30 volume % hydrogen, under practically anhydrous conditions at temperatures of 390.degree. to 540.degree. K., under pressures of 1 to 300 bars in the presence of a catalyst system containing nickel or nickel compounds, iodine and/or its compounds as well as a tertiary or quaternary organic nitrogen, phosphorus, arsenic or antimony compound. More particularly a catalyst system is used which contains vanadium or niobium or a compound thereof as an additional constituent.

Process for making acetic anhydride

The disclosure relates to a process for making acetic anhydride by reacting methyl acetate and/or dimethylether with carbon monoxide, if desired in admixture with up to 20 volume % hydrogen, under practically anhydrous conditions at temperatures of 120.degree. to 270.degree. C., under pressures of 1 to 500 bars in the presence of a catalyst system containing nickel or a nickel compound, an organic iodine or bromine compound as well as a tertiary or quaternary organic phosphorus compound. More particularly, a catalyst system containing a titanium or zirconium compound as an additional constituent is used.

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Bornheim, Germany

Erhard Jagers