DE2358355B2 - PROCESS FOR THE PRODUCTION OF 1,3-DIAMINO-2,2-DIMETHYLPROPANE - Google Patents

Description

Products Salary in Area percentage leader 15.7 1,3-diamino-2,2-dimethylpropane 71.1 l-amino-3-hydroxy-2-2-dirnethyl- 6 2 propane Neopentyl glycol 5.1 trailing 1.8

Thus, with a 94.9% turnover, based on neopentyl glycol, 71.1% of the desired 1,3-diamino-2,2-dimethylpropane.

From the raw filtrate it was then possible to use upstream and downstream Feiridestülatinr; Separate 548 g of the diamine in the boiling range from 154 to 156 ° ^C. at normal pressure. This amount corresponds to 73.7% of that which can theoretically be expected from the converted neopentyl glycol

Example 2

As in Example 1, 800 g of neopentyl glycol were reacted in a 10-1 steel autoclave in the presence of 80 g of a commercially available chromium-nickel catalyst. The catalyst consists of 52% nickel, with 30 parts by weight of chromium (III) oxide being accounted for per 100 parts by weight of nickel. Diatomaceous earth is used as the carrier in an amount of 50 parts per 100 parts of nickel. Here, too, pushes the recovery of the catalyst 20 atmospheres hydrogen gas and heated for 2 hours at 25O ⁰ C.

The crude filtrate separated from the catalyst has the following composition:

A 87.5% strength ^s conversion, based on neopentyl glycol with a selectivity of 50.2% to l, 3-diamino-2,2-dimethylpropane hereinafter were obtained. Work-up by distillation according to Example 1 gave 392 g of the diamine, corresponding to 57% of the theoretical amount to be expected from the reacted neopentyl glycol.

Example 3
lo

As in Example 1, 312 g of neopentyl glycol and 31 g of one were placed in a 10-1 steel autoclave commercially available chromium-nickel catalyst. 1700 g of liquid ammonia were then pumped into the pressure vessel. To activate the contact, a further 20 atmospheres of hydrogen were injected and the mixture was then heated for 3 hours to 240 ° C. After the autoclave had cooled and let down, the gas phase was removed and filtered from the catalyst. The composition of the Ronnitrates gave the following gas chromatography Analysis:

Products

Salary in
Area percentage

leader 11.6 1,3-diamino-2,2-dimethylpropane 50.2 l-amino-3-hydroxy-2,2-dimethyl- 21.8 propane Neopentyl glycol 12.5 trailing 3.9

Products

Salary in
Area percentage

leader 13.1 1, S-Diamino ^^ - dimethylpropane 80.6 l-Am: no-3-hydroxy-2,2-dimethyl- 7.6 propane Neopentyl glycol 1.5 trailing 0.2

Thus, a 98.5 ° / _o acetic conversion, based on neopentylglycol results. Work-up by distillation by pre-distillation and fine distillation according to Examples 1 and 2 led to 235 g of diamine. This corresponds to an amount of 78% of theory.

The 1-amino-3-hydroxy-2,2-dimethylpropane obtained during the reaction can - as well as the unreacted neopentyl glycol - in the process are recycled and is also in the pressure ammonolysis in 1,3-diamino-2,2-dimethylpropane converted, which makes the process particularly economical.

Claims (4)

2 claims: that the conversion of neopentyl glass, kol to the corresponding diamine by pressure ammonolysis 1. Process for the preparation of 1,3-diamino has not yet been attempted. This diamine 2,2-dimethylpropane, characterized by it, has been characterized so far by reacting acetone with the fact that neopentyl glycol, ammo-5 nitroipethane to 2,2-dimethyl-1,3-dinitropropane and niac and hydrogen at 220 to 300 ⁰ C and with hydrogenation of the dinitro compound (S. JACS a pressure of at least 10 at in the presence 71, p. 3249 [1949]). a catalyst of 23 to 60 percent by weight Da neopentanediamine, among other things, a valuable one Nickel deposited on a carrier material as an intermediate product for the production of polyurethane and optionally 16 to 40 percent by weight io thanene was a technically simple process too Contains chromium, converts. its manufacture from the easily accessible 2. The method according to claim 1, characterized in neopentyl glycol desired. It has now been oversubscribed that the process at 240 to 260 ° C surprisingly found that the above bed carried out, wrote side reactions largely in favor 3. The method according to claim 1, characterized in that the diamine formation can be suppressed, characterized in that a molar ratio of 1: 4 to _{1:40 is maintained so that this compound is maintained with the aid of special catalysts OH: NH 3.} in compliance with certain procedural 4. The method as claimed in claim 3, characterized in that the characteristics are produced directly from neopentyiglycol draws that m. η can become a molar ratio of. OH: NH ₃ from 1: 6 to 1:20 maintains. The invention relates to a method for Manufacture of!, S-Diamino ^^ -dimethylpropane, that characterized in that neopentyl glycol, It is known, diamines from dihydric alcohols ammonia and hydrogen at 220 to 300 ° C and to manufacture, e.g. B. one wins according to US-PS 31 37 730 under a pressure of at least 10 at in counter- Ethylenediamine from ethylene glycol and ammonia on 25 wart a catalyst that is 23 to 60 percent by weight Cobalt and nickel as well as copper containing nickel deposited on a carrier material Catalysts. Dk production of hexamethylene and optionally 16 to 40 percent by weight of chromium diamine from 1,6-hexanediol, ammonia and water contains, converts. material of nickel or cobalt-containing catalyst. It has been found advantageous to maintain a temperature iators is described in US Pat. No. 3,268,588. 30 temperature of 240 to 26O ⁰ C proved. According to DT-OS 19 53 263, polyalcohols, particularly suitable are catalysts that are in addition to in particular various glycols, optionally 16 to 40 percent by weight through conversion of nickel of ammonia on a cobalt, nickel or copper may contain chromium, which is inbcsondeie as Cr ₂ O ₃ containing catalyst is present to the corresponding in the catalyst. The catalyst is Amines are implemented. Appropriately kieselguhr added. He can next The DT-AS 11 72 268 contains a process for SiO ₂ still aluminum oxide and magnesium oxide Production of diamines from divalent aliphatic holdings. table alcohols and ammonia in the presence of The molar ratio OH: NH ₃ is not critical, Hydrogen at a temperature of 150 to 300 ° C, however, is useful in the process according to the and a pressure of at least 10 at with nickel 40 invention a molar ratio OH: NH ₃ of containing catalysts. Maintain 1: 4 to 1:40. Is particularly cheap Not all deaco alcohols can be determined by the known molar ratio of OH: NH ₃ from 1: 6 to Implement pressure ammonolysis, since the bilateral reac- 1: 20. tion of α, ω-diols no uniform reaction with the process according to the invention mechanism is subject. Depending on the position of the 45 yields of 1,3-diamino-2,2-dimethylpropane of the two hydroxyl groups to one another are obtained below - more than 50%. different reaction products. From propane-l, 3-diol The reaction can be discontinuous or continuous could be carried out, as can be done through our own experiments with nickel, Catalysts could be determined, the diamine The following examples serve to illustrate only obtained in amounts below 1%, since 50 of the invention, apparently by / 3-elimination of a hydroxyl group Example 1
intermediate allyl alcohol occurs, which is largely too primary and secondary propylamine reacted. 800 g of Neopenwird were placed in a 10-1 steel autoclave. In addition, considerable amounts of tylglycol and 80 g of a commercially available nickel hydrocarbon are produced. 55 catalyst. The catalyst consists of 55 % nickel With neopentyl glycol, which is more stable than propane-1,3-diol as well as Al ₂ O ₃ and kieselguhr as carrier material. It is, cannot be dehydrated by /? - Elimination contains 10 parts of Al ₂ O ₃ per 100 parts of nickel and can take place, however, by dehydration of 50 parts of diatomaceous earth. It was first heated to 70 ° C. hydroxymethyl group to form the aldehyde group hydroxyl and then 1600 g of ammonia were formed by means of pressure pivalaldehyde. A pump could also be used in the steel vessel. In addition, the aldol cleavage to formaldehyde and isobutyraldehyde was injected with 20 atmospheres of hydrogen gas and the temperature was expected to be 4 hours. The fragments formed in this way are heated to 245 ^° C. with vigorous stirring. An operating pressure of 300 atmospheres can then be established in the reaction medium.
The ammonia and hydrogen gases present were filtered while the pressure reactor was still cooling and long-reducing amination to methylamine and iso-65 samememememememememememememememememememememememememememememememememememememememememememememememememallemgmemerme) as possible with the conversion of the butylamine. Contents of the autoclave through a Seitz filter. The gaschro- From the observational analysis of the filtrate reproduced above, the verifiable genes and considerations can probably be explained by standing result on: