DE1568164A1 - Process for the catalytic hydrogenation of diaminodiphenylalkanes or ethers - Google Patents

Description

BADISCHB AHILIIi- & SODA-FABRIK AG

Our symbols 5 OZ 24 428 Bk / Kn Ludwigshafen / Rhein, August 19th * 1966

-. Process for the catalytic hydrogenation of diaminodiphenylalkanes or ethers

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Addendum to patent. ., .. *. (Patent application B 86 109 ITb / 12 0)

Subject of the patent. . «.. Λ .. · (patent application B 86 109 IVb / 12 0) is a process for the catalytic hydrogenation of diaminodiphenylalkanes or" ether in the presence of known hydrogenation catalysts "such as copper;, chromium, manganese, tungsten, Mo- = LyMän, Kohalt or Kfiekel, without the addition of alkaline earth oxides in inert solvents at elevated temperature and pressure, at which the inert solvent is cyclic ethers with K an oxygen atom in the ring or cyolohexylamine in concentrations of 30 to 90 wt .- #, based on the sum of solvents and the compound to be hydrogenated, is used.

It has now been found that the process according to the main patent can be further developed by adding N-alkylated cyclohexylamines all inert solvents instead of cyclic ones

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Ethers with an oxygen atom in the ring or cyclohexylamine are used.

Just like "with the method according to the main patent, the Hydrogenation of diaminodiphenylalkanes or ethers in high yield. When using N-alkylated cyclohexylamines fin-} det decomposition of the solvent takes place only to a particularly small extent during the hydrogenation.

With regard to the starting materials and the reaction conditions soh like the amount of solvents used, the present process does not differ from the process according to the main patent.

Preferred UT-alkylated cyclohexylamines are those which are substituted once or twice on the nitrogen by alkyl groups of 1 to 4 carbon atoms, such as ethyl, methyl, isopropyl or butyl radicals; suitable compounds are, for example, H-methyloyolohexylamine, NjN-diethyloyclohexylamine BT-methyl-N-butylcyclohexylamine, U-isopropyicyclohexylamine. The preferred IT-alkyl-substituted cyclohexylamines can also be used in combination with the inert solvents described in the main patent. It is particularly advantageous to use a mixture: of N-alkyl! ert en Cyolonexylaainen and the products as a solvent te · η. In addition, it is by no means necessary that the solvents used are absolutely anhydrous . Even

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With water contents "up to 2% by weight" based on the solvent, the hydrogenation still succeeds in excellent yield.

The parts given in the following example are parts by weight. They relate to parts of space as g to cm-.

example

A vertical high-pressure tube is charged with 1 Räumteii of a catalyst, consisting of 25 wt .- # Cobaltoxyä, atif pumice. The catalyst is then reduced in the course of 60 hours at 320-340 ⁰ O without pressure with hydrogen. 0.150 parts by volume of a mixture of 30 parts by weight of 4,4'-diamino-3,3'-dimethyldiphenylmethane and 70 parts by weight of N-dimethylcyciohexylamine and 150 parts by weight of hydrogen are then metered into the head of the high-pressure tube every hour. The reaction conditions are 220 to 225 ° 0 and 300 atm. The reaction mixture is discharged at the lower end of the high-pressure tube and separated from the excess hydrogen in a separator. The hydrogen saturated with Ν, Ν-dimethyloyclohexylamine is combined with fresh hydrogen and fed back into the high pressure tube. Of 1000 parts of the discharged reaction mixture 690 parts ₁ If N-dimethylcyclohexylamine and 310 parts of crude is obtained by fractional distillation of 4,4-Dii & mino-3,3-dimethyldicyclöhexylmethan from kpq ~ "144 ⁰ O. The crude mixture

/ 4 009848/1859 8AD orjginal

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"consists of 87 wt .- ^ 4,4 ⁱ ~ diamino ~ 3» 3 ° "= dicyclohexylmethane, 10 wt .- # 4,4'-diamino-3'-dimethylphenylcyclohexylmethane and 2 wt .- ^ of a non-distillable Residue. The 4.4 ³ »Μ-amino-3,3 '," the hydrogenation is dimethylphenylcyclohexylmethan fed back. The yield, "based on 4» 4 ⁹ -'Diamino-3,3'-dimethyldiphenylmethane, is 97 ¥> of theory.

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Claims (1)

O.Z. 24 428 Patent entitlement Further embodiment of the process for the catalytic hydrogenation of diaminodiphenylalkanes or ethers in the presence of known hydrogenation catalysts, such as copper, chromium, manganese, tungsten, molybdenum, cobalt or nickel, without the addition of Brdalkalioxyden in inert solvents at elevated temperature and pressure, in which one as inert solvents cyclic ethers with an oxygen atom in the ring or cyclohexylamine in concentrations of 30 to 90% by weight, based on the sum of solvents and compound to be hydrogenated, used according to patent. ...... (patent application B 86 109 I Vb / 12 o), characterized in that N-alkylated cyclohexylamines are used as inert solvents instead of cyclic ethers with an oxygen atom in the ring or cyclohexylamine. BADISOHE ANILIN- & SODA-FABRIK AG ( ^BATH ORIGINAL 009848/1859