JPS6045583A - Sugar alcohol ketal compound of triacetonamine - Google Patents

Abstract

NEW MATERIAL:The compound of formula (R is H, lower alkyl or lower alkanoyl; R1 is sugar alcohol residue; n is 1 or 2). EXAMPLE:Triacetonamine xylite monoketal. USE:Useful as an excellent light stabilizer for synthetic polymers such as polyolefin, styrene resin, etc. and various other organic materials, an active component for pharmaceutical and agricultural use, and their synthetic intermediate. PREPARATION:The compound of formula can be prepared e.g. by reacting 2,2,6, 6-tetramethyl-4-oxopiperidine or its acid addition salt (e.g. salt with hydrochloric acid, sulfuric acid, p-toluene-sulfonic acid, etc.) with a sugar alcohol in the presence of an organic solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides novel 2,2.6.6-tetramethyl-4-
The present invention relates to oxopiperidine ketal derivatives, and specifically relates to sugar alcohol ketal derivatives of 2,2,6,6-tetramethyl-4-oxopiperidine useful as light stabilizers for organic materials such as synthetic polymers or intermediates thereof.

2.2.6.6-Titraalkylpiperidine Compounds are:
It is known as a light stabilizer for various organic materials including synthetic polymers such as polyolefins, polyurethanes, and styrene resins, and various ketal derivatives of 2゜2.6.6-tetraalkyl-4-oxopiperidine are also used. Are known.

For example, Japanese Patent Publication No. 54-16980 describes ketal derivatives of ethylene glycol or propylene glycol, Japanese Patent Publication No. 54-20977 describes ketal derivatives of trimethylolalkanes, and Japanese Patent Publication No. 561-26270 describes ketal derivatives of trimethylolalkanes. The publication describes ketal derivatives of ditrimethylolalkanes.

However, when the compounds described in these publications are used as light stabilizers for organic materials, their effectiveness is rapidly lost during formulation and use, and as a result, it is difficult to stabilize organic materials for a long period of time. I couldn't do it.

As a result of repeated research on tetraalkylpiperidine derivatives, the present inventors have discovered that a novel 2,2.6.6-tetramethyl-4-oxopiperidine ketal derivative represented by the following general formula (1) can be used as an organic material. It was discovered that it is extremely effective as a light stabilizer.

(In the formula, R represents a hydrogen atom, a lower alkyl group, or a lower alkanoyl group, R1 represents a sugar alcohol residue, and n represents 1 or 2.) In addition, the present invention represented by the above general formula (I) 2゜2.6.
6-Tetramethyl-4-oxopiveridine ketal derivatives (sugar alcohol ketal compounds of triacetonamine) are useful as active ingredients for pharmaceuticals and agricultural chemicals, or as intermediates for their synthesis.

In the triacetonamine sugar alcohol ketal compound of the present invention represented by the above general formula (N), the lower alkyl group represented by R, such as methyl, ethyl, propyl,
Examples of the lower alkanoyl group include isopropyl, butyl, sec-butyl, tertiary-butyl, and isobutyl, and examples of the lower alkanoyl group include acetyl and propionyl.

As the sugar alcohol residue represented by R1, for example, D
, L-) Reit, Erythri Nodo, D, L=Near Rabbit Rivit, Xylit, D, L-Sorbit, D,
Examples include residues such as L-mannite, D, L-i';t, D, L-talit, dulcit, and ali.

Specific examples of the compound of the present invention represented by the above general formula (I) include the following, but the compound of the present invention is not limited thereto.

Triacetonamine xylit monoketal, triacetonamine D-sorbisoto diketal, triacetonamine D-mannit moketal, triacetonamine D-mannitol monoketal, N-butyl triacetonamine D -Mannitol monoketal, triacetonamine dulsisotodiketal, triacetonamine erythritisodiketal, N-methyltriacetonamine erythritisodiketal, N-acetyl TAA
・Erythritisodiketal, N-propionyl TAA・
Erythritol diketal.

The compound of the present invention represented by the general formula (1) is, for example, 2,2,6,6-tetramethyl-4-oxopiperidine (triacetonamine) or its acid (hydrochloric acid, sulfuric acid,
It can be easily produced by reacting an addition salt (P-) luenesulfonic acid, etc.) with a sugar alcohol in the presence of a solvent and a solvent.

The present invention will be explained in more detail below with reference to Examples, but the present invention is not limited by these Examples.

Example 1 Synthesis of triacetonamine xylitol monoketal 20.0 g of xylit and 33.0 g of triacetonamine sulfate were mixed in toluene/n-hexane (3/1).
The mixture was added to 80 ml of the mixture, heated under a nitrogen stream, and reacted for 4 hours while distilling off the water produced azeotropically under n-hexane reflux. Sampling was performed, and after neutralization with alkali and gas chromatography to confirm that no triacetonamine remained, the sample was neutralized with a 20% NaOH aqueous solution. After cooling sufficiently, oil and water are separated, and the organic layer is further separated into two layers.
After washing twice with water, the aqueous layers were combined and extracted several times with chloroform.

After drying with anhydrous sodium sulfate, the solvent was removed to obtain a highly viscous crude ketal.

Silica gel chromatography gave a slightly yellowish brown waxy triacetone amine xylitol monoketal.

Amine value 4.87% (theoretical value 4.84%) IR110
0cm' Ketal appearance High performance liquid chromatography 0ne-peak Example 2 Synthesis of triacetonamine/D-sorbisoto diketal 38, 3 g of triacetonamine hydrochloride and 18.2 g
of D-sorbitol in 100+nl of 5ec-butanol/n-hexane (3/1). The reaction was carried out using 1 g of concentrated sulfuric acid as a catalyst. The reaction was carried out for 6 hours while removing the produced water which azeotroped with n-hexane from the system.

After cooling to about 50°C, it was neutralized with a 25% Na0II aqueous solution, and the alkaline aqueous layer was separated. After further washing with warm water, the IJ31 layer was desolvated using a rotary evaporator to obtain 43.3 g of crude ketal as a pale brown solid.

This crude ketal has a mp35-38°C1 amine value of 5.8
It was 7% (theoretical value 6.14%). The monoketal was separated by mass preparative liquid chromatography to obtain triacetonamine-0-sorbi, todiketal as a slightly yellowish brown solid.

mp 43-44℃ Amine value 6.09% (theoretical value 6.14%) IR170
0 cm (C=O disappearance 1100 cm-1 Ketal appearance Liquid chromatography 0ne-peak Example 3 - Synthesis of triacetonamine D-mannisoto diketal 23, 0 g triacetonamine hydrochloride, 10.9 g
A mixture of D-mannite, 1.0 g of p-1-luenesulfonic acid, and 60 ml of toluene was heated under a nitrogen stream,
Dehydration reaction was carried out under toluene reflux. After the theoretical amount of produced water had been distilled off, the liquid temperature was cooled to about 50° C., neutralized with an excess amount of aqueous potassium hydroxide solution, and washed with water. Dehydration was performed under refluxing toluene, and upon cooling, a slightly yellowish brown solid precipitated. After filtration and drying, a crude ketal was obtained. Triacetonamine-D-manninotodiketal was obtained using a silica gel column.

mp 190.5-191. '5℃ Amine value 6.12% (theoretical value 6.14%) IR170
0cm-I C=O disappearance 1100cm' Ketal appearance High performance liquid chromatography 0ne-peak Example 4 Synthesis of triacetone amine D-mannite monoketal 18, 2 g D-mannit, 19.2 g triacetone 100ml of amine hydrochloride and 0.6g concentrated sulfuric acid
The mixture was added to n-hexane, heated under a nitrogen stream, and reacted for 3 and a half hours while excluding the water produced azeotropically under reflux of n-hexane. After neutralization with 28% CH3ONa/CH30H,
Insoluble matter was filtered off and the solvent was removed. After several extractions with hot MSP and cooling, the crude ketal is obtained, mp 136.5-1
38℃ Amine value 4.41% (theoretical value 4.39%) IR170
0cm-I C=O disappearance 1100cm4 Ketal appearance High performance liquid chromatography 0ne-peak Example 5 Synthesis of N-butyltriacetonamine/D-mannitol monoketal 18.6g of triacetonamine, 18.2g of potassium carbonate and 1.8 g of sodium acetate was added to 100 ml of toluene and 18.1 g of butyl bromide was added dropwise at 50-55°C. After dropping, raise the temperature to 95-100
'C for 10 hours. The produced inorganic substance was filtered, the solvent was removed, and the mixture was extracted with hot toluene, dried over anhydrous sodium sulfate, and the solvent was removed to obtain N-butyltriacetonamine. 21.
8 g of D-manniso), 1.2 g of para-toluenesulfonic acid, 801 of 5ec-butanol and 20 ml of n-
Hexane was added and ketalization was performed in the same manner as in Example 4 to obtain crude N-phthyltriacetonamine/D-mannitol monoketal. Purification by silica gel chromatography gave a pale yellow oil.

Amine value 3.73% (theoretical value 3.73%) T R2B
00cm' N-Cl+2- appearance 1095cm' Ketal appearance 1700cm-IC=O disappearance High performance liquid chromatography 0ne-peak Example 6 Synthesis of triacetonamine dulsisoto diketal 24.8g of triacetonamine was added to 60ml of butyl cellosolve and 20 ml of n-bexane, and 16.2 g of 36% hydrochloric acid was added dropwise while cooling. After the dropwise addition was completed, the mixture was heated under a nitrogen stream, and a dehydration reaction was performed under reflux of n-hexane. Once the theoretical amount of produced water has been distilled out, cool it down.
Add 14.6 g of dulcit and 1.3 g of para-toluenesulfonic acid, warm again, and reflux the n-hexane for 6 hours.
Time reacted. After neutralization with a 10% Rol+ aqueous solution and separation of oil and water, the organic layer was desolvented and recrystallized with MSP to obtain triacetonamine dulcisoto diketal as a white solid.

mp 291℃ (by differential heat) Amine value 6.12% (theoretical value 6614%) IR170
0 cm-I C=O disappearance 1100 cm-' Ketal appearance High performance liquid chromatography 〇ne-peak Example 7 Synthesis of triacetonamine/erythritisot diketal Add 60 ml of xylene to 11. ．． 5 g of triacetonamine hydrochloride and 6.1 g of erythritol were added, heated while blowing hydrogen chloride gas, and heated to 8.0 g while distilling off the water produced.
A time reaction was performed. Cool to about 50℃ and add 28% CH3O
Na/CH30H was added to neutralize to pH 8-9, and insoluble materials were filtered. The filtrate was reduced to pA7 using a rotary evaporator.
44 medium to obtain 18.7 g of crude ketal (yield 94%). A white solid of triacetonamine erythritol diketal was obtained by recrystallization with xylene.

mp 117-119℃ Amine value 7.01% (theoretical value 7.04%) TR325
0cm-1-OH disappears 1050c+n-' -OH disappears 3400cm' NH appears 1100cll Ketal appears High performance liquid chromatography 0ne-peak Example day Synthesis of N-methyltriacetonamine erythritol dione 15.9g of triacetonamine. Erythritisodiketal, 3.3g of paraformaldehyde was added to 50+nl of 1-toluene and slowly warmed. It became uniform at 55°C. 5. 80% formic acid while keeping the liquid temperature at 85-90°C.
5 g was added dropwise over about 1 hour.

At this time, be careful about the dropping speed as heat generation and foaming occur.

After the dropwise addition was completed, the temperature was raised and the mixture was reacted for 4 hours under toluene reflux. After cooling to 80''c, the mixture was neutralized with NaOH, washed with water, separated from oil and water, and the toluene layer was desolvented to obtain colorless viscous liquid N-methyltriacetonamine/erytrinodiketal.

Amine value 6.61% (theoretical value 6.60%) I R28
20cm"' N-CH3 appearance Example 9 Synthesis of N-acetyl TAA/erythritisodiketal 8, Og TAA/erythritisodiketal, 3°5g
of pyridine was added to 20 ml of benzene, and while cooling, a solution of 3.5 g of acetyl chloride dissolved in 10 ml of benzene was added dropwise, and the mixture was allowed to stand overnight at room temperature. The reaction mixture was placed in ice water and made weakly alkaline with an aqueous sodium carbonate solution.

After drying the benzene layer with anhydrous sodium sulfate, the solvent was removed to obtain white crystals. Purified through an alumina column and N-acetyl T
AA. erythrinotodichale was obtained.

mp 111~l 12.5°d Amine value 0% IR' 3250cm-1C N-11 Disappearance 1635c
m', vCO-N Appearance NMR Confirmation of acetylated product Example 1O Synthesis of N-7''tffhionyl TAA/Elitelisotodiketal 19.9 g of TAA/Erytrisotodiketal, 52.
0 g propionic anhydride, 7.9 g pyridine and 20
0ml (7) xylene was reacted at 130-140°C for 5 hours. Water and chloroborum were added to the residual aroma after removing the solvent and dissolved, and then the oil and water were separated and the chloroborum layer was collected. The aqueous layer was further extracted with a small amount of chloroform and combined with the previous chloroform. After drying with anhydrous sodium sulfate, the solvent was removed to obtain white solid N-propionyl TAA/erythritol digatal.

mp 88-90°C Amine value 0% TR3250cm-1 disappearance 1635cm→appearance The effect of the compound of the present invention as a light stabilizer will be specifically explained using experimental examples using NMRN-propionylation as a confirmation method.

Experimental example 100 parts by weight of polypropylene, stearyl-β-3,5
Using 0.2 parts by weight of di-tert-butyl-4-hydroxyphenylpropione and 0.3 parts by weight of the sample compound, a sheet having a thickness of 0.3 mm was prepared by press working.

A light resistance test was conducted using this sheet using a high-pressure mercury lamp.

The results are shown in the table below.

Continuing from page 1 ■ Int, C1, 4 identification symbol Office serial number @ inventor
Fumi Hirai 5-2 Shirahata, Urawa-shi, In-house @ Inventor Shiba 1) Toshi Hiroshi Shirahata 5-2, Urawa-shi In-house @ Inventor Ryo Osamu Kimura In-house 13, 5-2 Shirahata, Urawa-shi Adeca Argus Chemical Co., Ltd. Association No. 13 Adeka Argus Chemical Co., Ltd. No. 13, Adeka Argus Chemical Co., Ltd.

Claims (1)

[Scope of Claims] A sugar alcohol ketal compound of triacetonamine represented by the following general formula (I). (In the formula, R represents a hydrogen atom, a lower alkyl group, or a lower alkanoyl group, R1 represents a sugar alcohol residue, and n represents 1 or 2.)