JPH0647604B2 - Polysaccharide derivative - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel polysaccharide derivative.

Aromatic carboxylic acid esters of polysaccharides, particularly highly substituted esters in which 50% or more of the hydroxyl groups in the polysaccharide molecule are substituted, are generally soluble in organic solvents and can be used as chromatographic carriers, liquid crystal substances, etc. However, only a very limited range of compounds have been synthesized so far.

That is, known compounds include cellulose benzoate, amylose benzoate, cellulose nitrobenzoate, cellulose aminobenzoate, cellulose p-phenylazobenzoate, cellulose o-acetyloxybenzoate and cellulose p-azito. Only synthetic examples of benzoate have been reported.

The present invention relates to a novel polysaccharide derivative different from the above-mentioned known polysaccharide aromatic carboxylic acid ester, in which 50% or more of the hydroxyl groups of cellulose are 3,5-dichlorobenzoyl group, m-chlorobenzoyl group, A polysaccharide derivative comprising an ester substituted with any one of p-chlorobenzoyl group, p-dimethylaminobenzoyl group and biphenylcarbonyl group, or an ester in which 50% or more of hydroxyl groups of mannan are substituted with benzoyl group.

As the reaction reagent for esterifying the above-mentioned polysaccharide and leading to the derivative of the present invention, the corresponding carboxylic acid anhydride or carboxylic acid halide may be used, and the reaction catalyst may be sulfuric acid, or Bronsted acid such as perchloric acid. Lewis acids such as zinc chloride, bases such as pyridine, triethylamine, and 4-dimethylaminopyridine can be appropriately used.

In the synthesis of the polysaccharide derivative of the present invention, as the raw material polysaccharide, one that is once dissolved in a solvent such as water or formic acid is precipitated in another solvent and dried, one obtained by directly freeze-drying the aqueous solution, or acetic acid. When a material obtained by hydrolyzing a polysaccharide ester such as an ester is used as a raw material, it has a large activity for the reaction and can be advantageously used.

The reactivity varies depending on the type of the polysaccharide and the degree of polymerization, but the degree of substitution of the polysaccharide derivative can be adjusted by selecting the reaction conditions.

The polysaccharide derivative of the present invention can be used in various forms. For example, it is used after being formed into a film shape, a fiber shape, a particle shape, or the like. In this case, the degree of polymerization is relatively high, for example, 6
It is preferably 0 or more in terms of physical strength of the molded product.

Further, in the case of being used by being supported on fine silica gel, those having a relatively low degree of polymerization, for example, those having a degree of polymerization of about 10 to 80 are more advantageous in terms of coating properties and the like.

As the polysaccharide derivative of the present invention, the tri-substituted product shown in the examples is excellent in organic solvent solubility and various functions. Further, the polysaccharide derivative of the present invention has a performance different from that of known cellulose benzoate in the function of separating optical isomers. That is, the optical isomers that cannot be separated by the cellulose benzoate ester can be separated, and only the isomers of the compound within a limited range can be separated until now, but the range can be expanded.

The present invention will be described below with reference to examples, but the present invention is not limited thereto.

Example 1 To 20 g of 3,5 dichlorobenzoic acid, 49.4 g of thionyl chloride and 0.21 m of pyridine were added, and the mixture was kept under reflux for 2 hours. Then, excess thionyl chloride was removed by distillation, dry hexane was added to the residue, insoluble matter was separated from the resulting solution,
When the hexane was removed under reduced pressure, the residual liquid crystallized. Crystal is 3,
It was 5-dichlorobenzoyl chloride, and the yield was almost quantitative.

The cellulose acetate was saponified with hydrazine, washed, replaced with acetone, and dried to obtain cellulose.

1.0 g of the above cellulose was reacted in a reaction solution consisting of 11.6 g of 3,5-dichlorobenzoyl chloride, 25 m of dehydrated pyridine, 4.3 m of triethylamine, and 50 mg of 4-dimethylaminopyridine, while maintaining the temperature at 100 ° C. for 5 hours. After the reaction solution was added to ethanol to cause precipitation, the product was washed with ethanol and dried under vacuum. A methylene chloride solution of the product was applied to sodium chloride, dried and subjected to infrared absorption spectrum measurement. The infrared absorption spectrum obtained is as shown in FIG. 1, and its characteristic absorption band is as follows.

3080Cm ^-1 aromatic C-H stretching vibration 1740 cm ^-1 skeleton vibration due to the expansion and contraction of the carbon and the carbon in the C = O stretching vibration 1570,1430,1400Cm ^-1 benzene ring of the carboxylic acid ester 1260 cm ^-1 C-O stretch of esters Vibration 1030 to 1160 cm ^-1 Cellulose C-O-C stretching vibration 660 to 900 cm ^-1 Benzene ring out-of-plane bending vibration Cellulose OH-based absorption near 3450 cm ^-1 is only slightly observed and almost 3 substitutions Indicates a body.

The characteristic absorption of the proton NMR spectrum measured in CDCl ₃ is as follows.

7.3 to 8.0 ppm Proton of benzene ring 3.4 to 5.8 ppm Intensity ratio of absorption of glucose ring of cellulose and proton of methylene at 6-position was 9: 7.

From these results, the product is cellulose-3,5 with a degree of substitution of 3.0.
-Identifiable as dichlorobenzoate.

Example 2 Cellulose acetate was saponified with hydrazine, washed, substituted with acetone and dried to obtain cellulose. This cellulose
3.0 g was suspended in a mixed solution of 50 mg of 4-dimethylaminopyridine, 50 m of dehydrated pyridine and 15 m of triethylamine, 25 g of m-chlorobenzoyl chloride was added, and the mixture was kept at 100 ° C for 6 hours. The reaction solution was added to ethanol, the formed precipitate was separated, washed repeatedly with ethanol, and dried in vacuum to obtain 9.1 g of a product.

A methylene chloride solution of the product was applied to sodium chloride, dried and subjected to infrared absorption spectrum measurement. The infrared absorption spectrum is as shown in FIG. 2, and its characteristic absorption band is as follows.

3070 cm ^-1 aromatic C-H stretching vibration 1740 cm ^-1 skeleton vibration due to the expansion and contraction of the carbon and the carbon in the C = O stretching vibration 1580,1480,1430Cm ^-1 benzene ring of the carboxylic acid ester 1250 cm ^-1 C-O stretch of esters Vibration 1060 to 1150 cm ^-1 Cellulose C-O-C stretching vibration 670 to 900 cm ^-1 Benzene ring out-of-plane bending vibration Cellulose OH-based absorption near 3450 cm ^-1 is hardly observed, and almost tri-substituted product Is shown. CDCl
The characteristic absorptions of the proton NMR spectrum measured in ₃ are:

7.0-8.5 ppm Proton of benzene ring 3.2-5.8 ppm Proton of glucose ring of cellulose and proton of methylene at 6-position The absorption intensity ratio was 12: 7.

From the above, the product can be identified as cellulose-m-chlorobenzoate having a degree of substitution of 3.0.

Example 3 Cellulose acetate was saponified with hydrazine, washed, replaced with acetone, and dried to obtain cellulose. This cellulose
2.43 g of pyridine 50 m, triethylamine 20 m
, 4-dimethylaminopyridine in 200 m was reacted with 15.75 g of p-chlorobenzoyl chloride under stirring at 110 ° C. for 8 hours. The product was added to 500 m of methanol, and the formed precipitate was separated, washed with water, washed with methanol, dissolved in benzene, and added to ethanol for purification by reprecipitation. A methylene chloride solution of the product obtained by separate vacuum drying was applied to a sodium chloride cell, dried and subjected to infrared absorption spectrum measurement. The infrared absorption spectrum thus obtained is as shown in FIG. 3, and its characteristic absorption band is as follows.

3100 cm ^-1 aromatic C-H stretching vibration 1720 cm ^-1 of the carboxylic acid ester C = O stretching vibration 1600,1490,1450,1400Cm ^-1 in the benzene ring of carbon and skeleton vibration 1260 cm ^-1 esters by stretching carbon C- O stretching vibration 1040-1160cm ^-1 Cellulose C-O-C stretching vibration 680-900cm ^-1 Benzene ring out-of-plane bending vibration Cellulose's OH-based absorption around 3450cm ^-1 is hardly observed, and almost It shows that it is a tri-substituted product. or,
The characteristic absorptions of the proton NMR spectrum measured in CDCl ₃ are:

6.5-8.5 ppm Proton of benzene ring 3.0-5.8 ppm Proton of glucose ring of cellulose and proton of methylene at 6-position The absorption intensity ratio was 12: 7.

That is, the product can be identified as cellulose-p-chlorobenzoate having a degree of substitution of 3.0.

Example 4 Endodon of ivory palm seeds is described in the literature [GO Aspinall, eta.
1J Chem. Soc., 3184 (1953)] to obtain a high molecular weight fraction of mannan B. 1.5g of this Mannan B powder
Then, 70 m of dehydrated pyridine, 7.7 m of dehydrated triethylamine and 50 mg of 4-dimethylaminopyridine were added, 10.7 m of benzoic acid chloride was added with stirring, and the mixture was reacted at 100 ° C. for 5 hours. After cooling, ethanol 400m
The product was added to the above with stirring to precipitate, filtered through a glass filter, and thoroughly washed with ethanol. After vacuum drying, it was dissolved in methylene chloride (30 m), insoluble matter was removed, and the residue was reprecipitated in 400 m of ethanol. The precipitate was filtered, washed with ethanol, and deliquored to dryness.

A methylene chloride solution of the product was applied to sodium chloride, dried and subjected to infrared absorption spectrum measurement. The infrared absorption spectrum thus obtained is as shown in FIG. 4, and its characteristic absorption band is as follows.

3070cm ^-1 Aromatic C-H stretching vibration 1730cm ^-1 C = O stretching vibration of carboxylic acid ester 1605,1495,1455cm ^-1 Skeletal vibration due to stretching of carbon and carbon in benzene ring 1270cm ^-1 C-O stretching vibration of ester 1030 to 1200 cm ^-1 Mannan C-O-C stretching vibration 690 to 900 cm ^-1 Benzene ring out-of-plane bending vibration Mannan OH-based absorption near 3450 cm ^-1 was hardly observed, and it was almost trisubstituted. is there. The characteristic absorption of the proton NMR spectrum measured in CDCl ₃ is as follows.

6.8 to 8.4 ppm Proton of benzene ring 2.8 to 6.0 ppm Proton of mannan ring and methylene at 6-position The absorption intensity ratio of each was 15: 7.

The product can be identified as a mannan benzoate with a degree of substitution of 3.0.

Example 5 p-Dimethylaminobenzoic acid 25.8 in 30 m of benzene
g was suspended, 16.9 m of thionyl chloride was added, and the mixture was stirred. The bath temperature was adjusted to 100 to 110 ° C. to drive off the solvent, thionyl chloride (20 m) was further added, and the solvent was distilled off while heating. Diethyl ether was added to the oily portion to solidify the desired hydrochloride of p-dimethylaminobenzoic acid chloride, which was thoroughly washed with ether and then vacuum dried.

Cellulose acetate was saponified with hydrazine, washed, replaced with acetone, and dried to give cellulose. This cellulose
70 g of dehydrated pyridine, 19.2 m of dehydrated triethylamine, 18.3 g of synthesized p-dimethylaminobenzoyl chloride hydrochloride and 50 mg of 4-dimethylaminopyridine were added to 1.5 g, and the mixture was stirred at 100 ° C. for 5 hours. The reaction solution was added to 400 m of ethanol to cause precipitation. Separated, washed well with ethanol and dried. This was dissolved in 100 m of methylene chloride, the insoluble material was removed by centrifugation and filtration, the solvent was evaporated to 30 m, and the residue was precipitated in ethanol, separated, washed well with ethanol, and then vacuum dried.

The product was dissolved in methylene chloride, applied to a sodium chloride cell, dried, and then subjected to infrared absorption spectrum measurement. The obtained infrared absorption spectrum is as shown in FIG. 5, and its characteristic absorption band is as follows.

3050cm ^-1 Aromatic C-H stretching vibration 2780cm ^-1 N-methyl group C-H stretching vibration 1710cm ^-1 C = O stretching vibration of carboxylic acid ester 1590,1490cm ^-1 Carbon and carbon stretching in benzene ring Skeletal vibration due to 1420 cm ^-1 CH symmetrical bending vibration of N-methyl group 1340 cm ^-1 OA stretching vibration of aromatic amine 1280 cm ^-1 ester stretching vibration VO 1060 to 1200 cm ^-1 Cellulose CO Stretching vibration of -C 690 to 900 cm ^-1 Out-of-plane bending vibration of benzene ring Absorption near 3450 cm ^-1 based on OH of cellulose is very weak, and it is considered that it is almost a tri-substitution product. The characteristic absorption of the proton NMR spectrum measured in CDCl ₃ is as follows.

2.9~3.2ppm N-CH ₃ protons respective absorption of the methyl protons 6.4~6.9,7.7~8.1ppm benzene ring proton 3.2~6ppm cellulose to glucose rings and 6-position methylene of intensity ratio for approximately 18: 12: 7 It was.

The product can be identified as cellulose-p-dimethylaminobenzoate with a degree of substitution of 3.0.

Example 6 Cellulose acetate was saponified with hydrazine, washed, replaced with acetone, and dried to obtain cellulose. This cellulose
To 0.7 g, 7.0 g of 4-biphenylcarbonyl chloride, 20 mg of dimethylaminopyridine, 10 m of pyridine and 3 m of triethylamine were added, and the mixture was maintained at 90 ° C for 5 hours while stirring, and 10 m of benzene was further added and kept at 90 ° C for 1.5 hours. The resulting dark brown reaction solution was added to 200 m of ethanol.

The formed cellulose precipitate was separated with a glass filter, washed repeatedly with ethanol and then with acetone, and dried under vacuum. 2.6 g of product was obtained.

A methylene chloride solution of the product was applied to a sodium chloride cell, dried and subjected to infrared absorption spectrum measurement. The infrared absorption spectrum obtained is as shown in FIG. 6, and its characteristic absorption band is as follows.

3030 cm ^-1 aromatic C-H stretching vibration 1720 cm ^-1 of the carboxylic acid ester C = O stretching vibration 1610,1560,1490,1450,1400Cm ^-1 in the benzene ring of carbon and skeleton vibration 1260 cm ^-1 esters by expansion and contraction of the carbon C-O stretching vibration 1050-1140cm ^-1 Cellulose C-O-C stretching vibration 700-900cm ^-1 Out-of-plane bending vibration of benzene ring Absorption around 3450cm ^-1 based on OH of cellulose is hardly recognized, It shows that the compound is almost trisubstituted. CDCl
The characteristic absorptions of the proton NMR spectrum measured in ₃ are:

6.8 to 8.5 ppm Proton of benzene ring 3 to 5.7 ppm Proton of glucose ring of cellulose and proton of methylene at 6-position The absorption intensity ratio was about 27: 7.

From the above, the product can be identified as a cellulose biphenylcarboxylic acid ester having a degree of substitution of 3.0.

[Brief description of drawings]

1 to 6 are views showing infrared absorption spectra of the products of Examples 1 to 6, respectively.

Claims (1)

[Claims] 1. 50% or more of hydroxyl groups of cellulose are substituted with any of 3,5-dichlorobenzoyl group, m-chlorobenzoyl group, p-chlorobenzoyl group, p-dimethylaminobenzoyl group and biphenylcarbonyl group. A polysaccharide derivative consisting of an ester or an ester in which 50% or more of the hydroxyl groups of mannan are substituted with a benzoyl group.