CS262797B1 - A method of preparing D-alose and D-altrose - Google Patents

Abstract

The purpose of the method for preparing D-allose and D-altrose is to improve the method for preparing these hexoses. The stated purpose is achieved by epimerization of D-glucose catalyzed by molybdate ions at elevated temperatures. The method of preparation of D-allose and D-altrose is used in organic chemistry.

Description

The invention relates to a process for the preparation of D-alose and D-altrose.

For the preparation of D-alose and D-altrose, the most common methods are based on the extension of the D-robose carbon chain by applying cyanohydrin synthesis [R. L. Whistler, M.L. Wolfrom: Methods Carbohyd. Chem. Vol. I, 102, Academic Press, New York-London (1962)] and nitromethane synthesis [V. Bilik: Chem. rumors 29, 114 (1975)]. Other methods of preparing D-alose and D-altrose are more complex. Suitable D-glucose derivatives are used. In liquid hydrogen fluoride, penta-O-acetyl- [beta] -D-glucopyranose is transformed into the corresponding derivative of D-mannose and D-altrose [C. Petersen: Acta Chem. Scand. 16, 1831 (1962)], octa-O-acetyl-lactose is transformed in the presence of aluminum chloride and phosphoropentachloride to the corresponding octa-O-acetylderivative of neolactose, which hydrolyzes to provide D-altrose and D-galactose [N. K. Richtmyer, Advan. Carbohyd. Chem. 17, 270 (1962)], also by hydrolysis of methyl 2,3-anhydro-4,6-O-benzylidene-α-D-allopyranoside, yields the corresponding D-altrose derivative [N. K. Richtmyer, C.S. Hudson:]. Amer. Chem. Soc. 63, 1727 (1941)]. By reduction of methyl β-D-dibohexopyranoside-3-ulose with Raney nickel or borohydride [P. J. Benyon, Μ. Collins, W.G. Overend: Why. Chem. Soc. 342 (1964)], optionally by a reduction of 1.2; 5,6-di-O-isopropylidene-α-D-dibohexulofuranose with lithium aluminum hydride [O. Theander: Advan. Carbohyd. Chem. 17, 270 (1952)], the corresponding D-altrose derivatives are formed. After acetolysis 1,2; 5,6-di-O-isopropylidene-α-D-allofuranose isolates D-altrose in 45% yields [W. Sowa: Can. J. Chem. 50, 1092 (1972)]. The possibilities of preparing D-alose are more limited. In addition to the preparation of cyanohydrin synthesis and nitromethane synthesis, D-alose is prepared from tetra-O-benzoyl-3-O-p-toluenesulfonyl- [beta] -D-glucopyranose by nucleophilic substitution of the tosyl group with sodium benzoate via penta-O-benzoyl-.beta.-D-alopyranose. [W. W. Zorbach, A.P. Ollapaly: J. Org. Chem. 29, 1790 (1964)] and molybdenum ion catalyzed epimerization of D-altrose [V. Bilik: Chem. rumors 29, 114 (1975)]. The proposed method allows the preparation of D-alose and D-altrose directly from D-glucose.

The principle of the preparation of D-alose and D-altrose consists in heating an aqueous solution of D-glucose at a pH of 2 to 5.5 with a catalytic effect of molybdenum ions at a temperature of 110 to 150 ° C for 1 to 5 hours.

An advantage of the proposed process for the preparation of D-alose and D-altrose is that a 12-17% yield of D-alose and D-altrose is obtained in a very simple manner by the epimerization of D-glucose and after fermentation of D-glucose and D-mannose. of these aldoses, the D-alose is separated by fractionation on the n-exchanger column with functional sulfo groups in the calcium or barium cycle by elution with water and D-altrose on the cellulose column. A further advantage is that the necessary chemicals are commercially available and the entire preparation process is unpretentious on the technological equipment.

Example 1

198 g of D-glucose monohydrate are dissolved in water and, after addition of 5 g of ammonium molybdate and 30 ml of 100% by weight. acetic acid) was added to a total volume of 600 ml with water and heated at 120 ° C for 2 hours. The reaction mixture is diluted with 1000 ml of distilled water and 1000 ml of drinking water and after addition of 30 g of yeast (Saccharomyces cerevisiae) the solution is fermented until the removal of D-glucose and D-mannose is complete (3 days). The solution is filtered, concentrated to 500 ml volume, treated with charcoal and concentrated. The syrup-like residue is chromatographed on an ion-exchange column (Ostion KS 0210) with functional sulfo groups in a calcium cycle of 3.6 cm in diameter and 110 cm in length eluting with water. Fraction 1 contains reverse products, fraction 2 of D-allose and D-altrose, and fraction 3 of D-allose. Refractionation of fraction 2 yielded an additional portion of D-allose. D-altrose is isolated from the remainder of fraction 1 by chromatography fractionation on a 4 cm diameter cellulose column 80 cm long using the n-butanol:: ethanol: water 5: 1:: 4 by volume system. Chromatographically pure aldoses are obtained by crystallization from alcohols. . D-alose by crystallization from methanol shows a melting point of 130 to 132 ° C and a specific rotation of [α] ²³ + 14.1 ° (c 2, water) and D-altrose by crystallization from absolute ethanol shows a melting point of 104 to 107 ° C and specific rotation [α] ²³ D -31.5 ° (c 2, water). The literature gives a melting point of 128 to 128.5 ° C and a specific rotation of [α] D ²⁰ + 14.4 ⁰ (c 1.3, water) for D-allose [FP Phelps, F. Bates: J. Amer. Chem. Soc. 56, 1250 (1934)] and for D-altrose, melting point 103-105 ° C and specific rotation [α] _D + 32.6 ° (c 7.6, water) [NK Richtmyer, CS Hudson: J. Amer . Chem. Soc. 57, 1717 (1935)]. The composition of the reaction mixtures as well as the purity of the isolated aldoses were monitored by chromatography on chromatography paper (Whatman No 1), eluting with an acetone: n-butanol: water (7: 2: 1 by volume) flow rate of 18 to 20 hours. glucose (1.00) for D-allose is 1.11, D-altrose is 1.64 and for D-mannose is 1.29. This procedure yielded 30.5 g, i.e., 16.9% yield of D-alose and D-altrose in a 3: 2 weight ratio calculated on the starting D-glucose.

Unless otherwise indicated, they are indicated by% -wt.

Example 2

The procedure is as in Example 1, except that acetic acid is not added and the mixture is heated at 120 ° C for 2 hours. 30 g of t is obtained. j. 16.7% of D-alose and D-altrose calculated on the starting D-glucose.

EXAMPLE 1 a d 3

The procedure was as in Example 1 except that the mixture was heated at 110 ° C for 5 hours. 23.5 g of t is obtained. j. 13.1% D-alose and D-altrose calculated on the initial D-glucose.

Example 4

The procedure is as in Example 1, except that 2.5 g of ammonium molybdate and 15 ml of 100% by weight are added. of acetic acid and heated at 130 ° C for 2 hours. 24.5 g of t is obtained. j. 13.6% D-alose and D-altrose calculated on the initial D-glucose.

Example 5

The procedure was as in Example 4 except that the mixture was heated at 150 ° C for 1 hour. 11 g of t is obtained. j. 11.7% D-alose and D-altrose calculated on the initial D-glucose.

Example 6

The procedure is as in Example 2 except that ammonium molybdate, but 3 g of molybdic acid is added and the mixture is heated at 120 ° C for 2 hours. 26.5 g of t is obtained. j. 14.7% of D-alose and D-altrose calculated on the initial D-glucose.

The invention may find use in the preparation of carbohydrates and carbohydrate derivatives.

Claims (1)

EXAMPLE 3 The procedure is as in Example 1 except that the mixture is heated at 110 DEG C. for 5 hours. There were obtained 23.5 g, i.e. 13.1% of D-aluminum and D-altrose calculated on the starting D-glucose. EXAMPLE 4 The procedure of Example 1 was followed except that 2.5 g of ammonium molybdate and 15 ml of 100 wt. acetic acid and the mixture was heated at 130 ° C for 2 hours. 24.5 g, i.e. 13.6% of D-alose and D-altrose are obtained, calculated on the starting D-glucose. Example 5 The procedure of Example 4 was followed except that the mixture was heated at 150 ° C for 1 hour. 11 g, i.e. 11.7% of D-alose and D-altrose are obtained, calculated on the starting D-glucose. EXAMPLE 6 The procedure is as in Example 2, except that ammonium molybdate but 3 g of molybdic acid are not added and the mixture is heated at 120 DEG C. for 2 hours. 26.5 g, i.e. 14.7% of D-alose and D-altrose, calculated on the starting D-glucose, are obtained. The invention may find use in the preparation of carbohydrates and carbohydrate derivatives. SUBJECT A method of preparing D-alose and D-altrose, wherein the aqueous solution of D-glucose at a pH of 2 to 5.5 is heated at 110 to 150 ° C for 1 to 10 hours under the catalytic effect of molybdenum ions molybdenum ions. 5 hours.