CS271983B1

CS271983B1 - 2,2,6,6-Tetramethyl-4-piperidyl] -2-propanone and its preparation

Info

Publication number: CS271983B1
Application number: CS888116A
Authority: CS
Inventors: Peter Rndr Danko; Ema Rndr Jexova; Alojz Balogh; Lubica Rndr Bzduskova
Original assignee: Danko Peter; Ema Rndr Jexova; Alojz Balogh; Lubica Rndr Bzduskova
Priority date: 1988-12-08
Filing date: 1988-12-08
Publication date: 1990-12-13
Also published as: CS811688A1

Abstract

RieSenie sa týká /2,2,6,6^tetrametyl- -4-piperidyl/-2-propanónu a sposobu jeho přípravy katalytickou hydrogenáciou 2,2,6,6-tetramety1-4-piperidylidénacetónu v atmosféře vodíka, v prostředí organického rozpúšíadla, pri teplote 20 až 120 C, pri atmosférickou! tlaku alebo pri tlaku do 5 MPa, v přítomnosti hydrogenačného katalyzátora, počas 1 až 72 h alebo redukciou 2,2,6,6-tetramety1-4-piperidylidénacetónu komplexným hydridom, v prostředí pyridinu, pri teplote 20 0 až 100 2C» počas 3 až 8 h. Procesy je možné uskutočňovat diskontinuitne alebo kontinuitne. 2,2,6,6-Tetrametyl- -4-piperidyl/-2-propanón je možné použil ako medziprodukt na výrobu vysokoúčinných svetelnýcn stabilizátorov polymérov a biologicky účinných látok, vrátane liečiv.The solution relates to /2,2,6,6^tetramethyl- -4-piperidyl/-2-propanone and a method for its preparation by catalytic hydrogenation of 2,2,6,6-tetramethyl-4-piperidylideneacetone in a hydrogen atmosphere, in an organic solvent environment, at a temperature of 20 to 120 C, at atmospheric pressure or at a pressure of up to 5 MPa, in the presence of a hydrogenation catalyst, for 1 to 72 h or by reduction of 2,2,6,6-tetramethyl-4-piperidylideneacetone with a complex hydride, in a pyridine environment, at a temperature of 20 0 to 100 2C» for 3 to 8 h. The processes can be carried out discontinuously or continuously. 2,2,6,6-Tetramethyl-4-piperidyl-2-propanone can be used as an intermediate for the production of highly effective light stabilizers of polymers and biologically active substances, including pharmaceuticals.

Description

CS 271983 B1

The invention relates to (2,2,6,6-tetramethyl-4-piperidyl) -2-propanone of formula (I)

CH CH.

CH.

CH 3 (I) 3 and its method of preparation. (2,2,6,6-Tetramethyl-4-piperidyl) -2-propanone is an intermediate for the preparation of high performance light stabilizers of polymers and biologically active substances, including drugs. From literature and industry, 2,2,6,6-tetramethyl-4-piperidone (triacetone amine) is known as the main starting product for the industrial production of polymer light stabilizers as well as a variety of polyalkylpiperidine based drugs. 3e Literature Synthesis / □. Am. Chem. Soc. 79, 5444, 1957, SU 520 357 DE 3525 385, " P 1627/1972] / detailed.

A novel derivative of tetramethylpiperidine, [2,2,6,6-tetramethyl-4-piperidyl] -2-propanone of formula I and its preparation by catalytic hydrogenation of 2,2,6,6-tetramethyl-4-piperidylideneacetone has now been found. under a hydrogen atmosphere, in an organic solvent environment, at a temperature of 20 ° to 120 ° C, at atmospheric pressure or at a pressure of up to 5 MPa, in the presence of a hydrogenation catalyst, for 1 to 72 hours, or reduction of 2,2,6,6-tetramethyl-4 - Piperidylideneacetone with complex hydride in pyridine at 20 ° C to 100 ° C for 3 to 8 h. For example, Raney-Nickel, Ni / AlgOg, Ni / Cr 2 O 3, palladium on support, platinum on support, can be used as the hydrogenation catalyst. , PtO2, other catalysts used in this purpose. Suitable complex hydride is, for example, LiAlH4,

Na BH 4, or NaAlH 2 / OCH 2 CH 2 OCH 3/2. Processes can be discontinuously or continuously. (2,2,6,6-Tetramethyl-4-piperidyl) -2-propanone of the formula I according to the invention can be used as an intermediate for the production of light stabilizers, suitable for thermoplastic polymer substrates such as polyolefins, polyesters, polyethers, polyurethanes, polystyrenes , the third. It is also suitable as an intermediate for the production of biologically active substances, including drugs.

The following examples illustrate, but do not limit the invention. Example 1

19.5 g (0.1 mol) of 2,2,6,6-tetramethyl-4-piperidylideneacetone dissolved in 150 ml of diethyl ether was weighed into a magnetic stirrer. κ solution was added 1.5 g Pd / Al 2 O 3 with a Pd content of 5% and the reaction mixture was vigorously stirred under a hydrogen atmosphere for 72 h at room temperature. After the reaction was complete, the catalyst was filtered off. After evaporation of the diethyl ether, the crude product was distilled under reduced pressure to collect the fraction having a boiling point of 71-2 ° C / 150 Pa from which 2,2,6,6-tetramethyl-4-piperidyl / 2-propanone was obtained as a weak yellow liquid. CS 271983 01

Elemental analysis for C 12 H 23 NO:

C, 73.04; H, 11.75;

Found: C, 73.14; H, 11.59;

7.10% N 7.03% N 1 H-NMR spectrum in CDCl 3: δ ppm / group 2.27 -ch 2 -co- 2.11 -co-ch 3 1.17 1.04 CH. 1.75 to 0.33 2 ^ -NH, -ch2 ·

1 M 2 H d 3 H with ax. 6 H with eg. 6 H s - CH - ring 6 H m IR spectrum, solution in CCl4: V> / C - 0 / - 1735 cm "1, O / NH / free - 3330 cm" 1, J "/ CH / n <a3 # 1380, 1365 cm -1, 9 / NH / viaz "3 430 cm -1 -1 Example 2

19.5 g (0.1 mol) of 2,2,6,6-tetramethyl-4-piperidylacetone were weighed into a 100 ml pressure vessel of an autoclave equipped with a stirrer, thermometer and pressure gauge, 45 ml of methanol and 0.6 g of Raney-Nickel catalyst were added . After the autoclave vessel was sealed, the reaction mixture was heated to 120 ° C and stirred for 1.5 h under a hydrogen pressure of 5.0 MPa. After completion of the reaction, the catalyst was filtered off, the solvent was distilled off under atmospheric pressure and the crude product was distilled under reduced pressure, collecting a fraction with a boiling point of 83-5 ° C / 400 Pa. A slightly colored, clear liquid of (2,2,6,6-tetramethyl-4-piperidyl) -2-propanone was obtained.

Elemental analysis for C 12 H 23 NO:

% C, 11.75; H, 7.10;

Determined: 72.87% C 11.53% H 7.03% N 1-NMR spectrum in CDCl 3 and X 3 - spectrum in CCl. were the same as in Example 1. Example 3

A flow hydrogenation reactor of 0.5 m length with an internal diameter of 25 mm was charged with 100 g of Ni-Cr 2 O 3 catalyst containing 60% Ni. After activation of the catalyst, a 30% solution of 2,2,6,6-tetramethyl-4-piperidylideneacetone in 2-propanol in a quantity of 250 g was fed into the reactor. h ”1, at a temperature of 70 ° C and a hydrogen pressure of 3.5 MPa. The crude product was distilled off under reduced pressure after the solvent was distilled off, and the safraction was collected at 71-2 ° C / 15OmP to give 2,2,6,6-tetramethyl-4-piperidyl-2-propanone as slightly colored liquid.

Claims

CS 271983 81 Elemental analysis for C 12 H 23 NO: Calculated: 73.04% C, 11.75% H, 7.10% N, determined: 73.11% C 11.54% H 7.06% N 1H - NMR and IR - EXAMPLE 4 3.8 g (0.1 mol) of NaBH4 were weighed into a 250 ml three-necked flask equipped with a stirrer, thermometer and dropping funnel and 150 ml of pyridine was added. After dissolution of NaBH4 in pyridine, 4.9 g (0.025 mol) of 2,2,6,6-tetramethyl-4-piperidylideneacetone were added dropwise over 1 h. The reaction mixture was then stirred at 100 DEG C. for 2 h. After completion of the reaction, 5% NaHCO 3 solution was added to the reaction mixture at room temperature, and after separation of the pyridine layer, the aqueous layer was extracted with n-hexane. After drying the combined organic solutions, n-hexane was distilled off in vacuo, pyridine at slightly lower pressure, and the crude product was distilled under reduced pressure with fraction withdrawal at 69-70.5 ° C at 100 Pa from which 2,2,6,6-tetramethyl-4-piperidyl] -2-propanone was obtained as a colorless liquid. Elemental analysis Calculated: 73.04% C 11.75% H 7.10% N Found: 72.87% C 11.68% H 7.06% N 1 H-NMR and IR spectra as in Example 1 (2,2,6,6-Tetramethyl-4-piperidyl) -2-propanone of formula (I)

2. A process for preparing 2,2,6,6-tetramethyl-4-piperidyl] -2-propanone according to claim 1, wherein the 2,2,6,6-tetramethyl-4-piperidylideneacetone is subjected to catalytic hydrogenation. in an atmosphere of hydrogen, in an organic solvent environment, at 20 to 120 ° C, at atmospheric! pressure or up to 5 MPa, in the presence of a hydrogenation catalyst, for 1 to 72 hours. CS 271983 B1

3. Preparation of (2,2,6,6-tetramethyl-4-piperidyl) -2-propanone according to claim 1, characterized in that the 2,2,6,6-tetramethyl-4-piperidylideneacetone is treated with with complex hydride, in pyridine medium, at 20 to 100 ° C, for 3 to 8 h