SU1715806A1 - Method of 5-hydroxy-2(5h)-furanon synthesis - Google Patents

Abstract

The invention relates to the production of lactones, in particular the preparation of 5-hydroxy-2 (5H) -furanone, which can be used in the synthesis of polymers, growth regulators, and herbicides. The goal is to increase the yield of the target product. The target product is obtained by oxidizing furfural NgOz at 20-60 ° C in the presence of catalytic amounts of 2-oxane naphthenate vanadium and hydroquinone in acetone, preferably at a molar ratio of furfural, H202, 2-hydroxynaphenate vanadium and hydroquinone 1: 3 , 03, 5): (0.003-0.001) :( 0.0003-0.001). The desired product was isolated from the reaction mixture by extraction after pretreating it with CaCO3 at 20-50 ° C. These conditions allow an increase in the yield of 5-hydroxy-2 (5H) -fusion from 50 to 90%. 2 tab. (Ls

Description

This invention relates to organic chemistry and concerns, in particular, a process for the preparation of 5-hydroxy-2 (5H) -furanone. which is used as an intermediate in the polymer system, growth regulators, herbicides.

The purpose of the invention is to increase the yield of the target product.

Example: In a three-necked flask equipped with a stirrer, reflux condenser) and a thermometer, 242 ml (3.3 mol) of acetone, 27.6 ml (0.33 mol) of furfural, 118 ml (1.1 mol) of 30% are placed In a visible hydrogen peroxide solution, 0.045 g (0.0001 mol) of vanadium 2-hydroxy naphthenate and 0.011 g (0.0001 mol) of hydroquinone are added.

The reaction mixture is heated in a water bath to 55-60 ° C for 6 h. Then, the oxygenate is cooled to room temperature, neutralized in a beaker with 40 g (0.4 mol) CAS0. filtered, evaporated to dryness under reduced pressure. The residue, in the form of a dark yellow oil, is extracted with several portions of sulfuric ether. The extracts are combined, treated with activated carbon and dried with anhydrous sodium sulfate. The solvent is distilled off.

Obtain 30.0 g of 5-hydroxy-2 (5H) -furanone (yield 90% of theory.), So pl. 55-57 ° C.

Found,%: C 47.84; H 3.93.

C4H40z

Calculated,%: C 48.00: H 4.00.

cl

00

about a

IR spectrum, cm4: 3520, 1796, 1767, 1635, -1115, 1010.

HMR spectrum, ppm: 5.44 (s, 1 H); 6.24 (p. 1H); 6.20 (d, 1H); 7.32 (d, 1H).

Table 1 presents the dependence of the yield of 5-hydroxy-2 (5H) -furanone on the reaction conditions and the amount of reagents.

The data show that the optimal process conditions are the reaction temperature, the amount of catalyst is 0.0003-0.001 mol / mol of furfural, the molar ratio of furfural — hydrogen peroxide 1: 3.2, and the molar ratio of catalyst — hydroquinone 1: one.

Table 2 presents the dependence of the yield of 5-hydroxy-2 (5H) -furanone on the temperature of the oxidizer during its treatment with CaCO3 and the amount of CaCO3.

Control over the complete consumption of Furfural, neutralization of calcium carbonate impurities is carried out using thin-layer chromatography on Silufol plates, mobile phase: acetone - chloroform in a 2: 1 ratio.

Thus, obtaining B-hydroxy-2 (5H} -furanone by the proposed method allows to increase the yield of the target product by 35-40%.

Claims (1)

The invention The method of producing 5-hydroxy-2 (5H) -furanone by oxidation of furfural with hydrogen peroxide at 20-60 ° C, characterized in that, in order to increase the yield of the target product, the oxidation is carried out in the presence of catalytic amounts of 2 o-saxifluethane vanadium and hydroquinone in acetone, followed by separation of the target product by extraction from the reaction mixture previously treated with calcium carbonate at 20-50 ° C. Table 1 Note. The oxidation temperature is 60 ° C, the molar ratio of furfural-hydrogen peroxide is 2-hydroxy-naphthenate vanadium-hydroquinone, 1: 3.2: 0.0003: 0.0003. table 2