1,3-Diethyl 2-oxopropanedioate

Clear yellow liquid

(Reaction at pH 5 to 8) (1) In 100 g of water, 30 g (0.187 mol) of diethylmalonate was suspended, the pH was adjusted to 10 with a few drops of a 5percent aqueous solution of sodium hydroxide and the liquid temperature was set to 10° C. (2) In another reactor, 45percent aqueous solution of sodium chlorate (402 g), 35percent hydrochloric acid (100 mL), and 35percent hydrogen peroxide (84 mL) were added while keep-ing at 35° C., and bubbling was performed by introducing air into the reactor so as to generate chlorine dioxide gas having a concentration of 8 vol percent and a purity of 99percent. (3) The introduction of chlorine dioxide gas generated in (2) above into the reactor of (1) above containing suspended diethyl malonate was started via an inlet tube, and the chlorine dioxide gas was blown into the reactor over 5 hours at from 13° C. to 18° C. while maintaining the pH at from 5 to 8 by the appropriate dropwise addition of the 5percent aqueous solution of sodium hydroxide. The amount ofthe 5percent aqueous solution of sodium hydroxide used was 180 g. (4) An aqueous solution of sodium thiosulfate was added to the homogeneous solution afier the completion of the reaction to reduce residual chlorine dioxide, and the extraction was performed with ethyl acetate. Ethyl acetate was distilled off from the extract by means of a rotary evaporator, and toluene was added to the residual oil obtained and dehydration was performed under reflux. Toluene was distilled off so as to obtain 28.9 g of diethyl ketomalonate (di- ethyl mesoxalate) as the desired product. The purity determined by gas chromatography was 99.7percent and the yield was89percent.10217] Diethyl ketomalonate (diethyl mesoxalate); ‘H NMR (300 MHz, CDC13) ö ppm: 4.39 (q, J6.0 Hz, 2H), 1.36 (t, J=6.0 Hz, 3H). ‘3C NMR (300 MHz, CDC13) ö ppm: 178.2, 160.2, 63.5, 13.9. GC-MS (El) mlz: 174 [M].The 30g (0.187mol) malonic acid diethyla ester aerosol in 100g water, to several drops of 5percent sodium hydroxide aqueous solution to regulate pH to 10, and become liquid 10 °C the rear, with the embodiment 1 also, blown to 8vol percent of the chlorine dioxide gas, into and through the appropriate 5percent aqueous sodium hydroxide solution in order to maintain the pH 10 at the same time in the vicinity of, the 13 °C -18 ° C temperature, lasted 5 hours blown into the chlorine dioxide gas. The use of 5percent aqueous sodium hydroxide solution to 180 g. After the reaction is finished, and the implementation reaction mixed solution treated in the same way, the target keto third acid di ethyl ester (diethyl oxalate in) 28.1 g. Gas chromatographic the measured purity is 88.1percent, the yield is 76percent. As an impurity containing a large amount of the 2, 2- two chlorine third b acid diethyl ester. 2, 2-diacid diethyla the ester is maletwo chlorine third known compound, the technical personnel in this field identifying the known method.(Reaction at pH 5 to 8) (1) In 100 g of water, 30 g (0.187 mol) of diethylmalonate was suspended, the pH was adjusted to 10 with a few drops of a 5percent aqueous solution of sodium hydroxide and the liquid temperature was set to 10° C. (2) In another reactor, 45percent aqueous solution of sodium chlorate (402 g), 35percent hydrochloric acid (100 mL), and 35percent hydrogen peroxide (84 mL) were added while keep-ing at 35° C., and bubbling was performed by introducing air into the reactor so as to generate chlorine dioxide gas having a concentration of 8 vol percent and a purity of 99percent. (3) The introduction of chlorine dioxide gas generated in (2) above into the reactor of (1) above containing suspended diethyl malonate was started via an inlet tube, and the chlorine dioxide gas was blown into the reactor over 5 hours at from 13° C. to 18° C. while maintaining the pH at from 5 to 8 by the appropriate dropwise addition of the 5percent aqueous solution of sodium hydroxide. The amount ofthe 5percent aqueous solution of sodium hydroxide used was 180 g. (4) An aqueous solution of sodium thiosulfate was added to the homogeneous solution afier the completion of the reaction to reduce residual chlorine dioxide, and the extraction was performed with ethyl acetate. Ethyl acetate was distilled off from the extract by means of a rotary evaporator, and toluene was added to the residual oil obtained and dehydration was performed under reflux. Toluene was distilled off so as to obtain 28.9 g of diethyl ketomalonate (di- ethyl mesoxalate) as the desired product. The purity determined by gas chromatography was 99.7percent and the yield was89percent. Diethyl ketomalonate (diethyl mesoxalate); ‘H NMR (300 MHz, CDC13) ö ppm: 4.39 (q, J6.0 Hz, 2H), 1.36 (t, J=6.0 Hz, 3H). ‘3C NMR (300 MHz, CDC13) ö ppm: 178.2, 160.2, 63.5, 13.9. GC-MS (El) mlz: 174 [M].make the 30g (0.187mol) malonic acid diethyla ester aerosol in 100g water, to several drops of 5percent sodium hydroxide aqueous solution to regulate pH to 10, and become liquid 10 °C. (2) in another reaction tank, in maintaining the temperature 35 °C at the same time, added 45percent aqueous solution of sodium chlorate (402g), 35percent hydrochloric acid (100 ml) and 35percent hydrogen peroxide (84 ml), into the air for bubbling, thereby generating concentration 8vol percent, purity 99percent of the chlorine dioxide gas. (3) through an introducing pipe, will begin the above-mentioned (2) in the introduction of the chlorine dioxide gas to the suspended with the above-mentioned malonic acid diethyl ester (1) in the container, and, through the appropriate drop in 5percent aqueous sodium hydroxide solution in order to maintain the pH 5-8 at the same time of, in the 13 °C -18 ° C temperature, lasted 5 hours blows into the chlorine dioxide gas. The use of 5percent aqueous sodium hydroxide solution to 180 g. (4) the aqueous solution of sodium thiosulfate is added to the reaction in the completion of the homogeneous solution, reducing residual chlorine dioxide, and using ethyl acetate extraction. From the obtained liquid extract rotary evaporator removed by distillation in ethyl acetate, toluene is added to the obtained residue in shape, carry out dehydration reflux. Distillation after removing toluene, the target keto third acid di ethyl ester (in oxalic acid diethyl ester, diethylmesoxalate) 28.9 g. Gas chromatographic the measured purity of 99.7percent, the yield is 89percent.Examples 3-7; To a 50 mL eggplant-shaped flask equipped with a magnetic stirrer, diethyl malonate (DEM), sodium chlorite (Na chlorite), acetic acid, sodium acetate (Na acetate), and water were put in the reaction scale and the molar ratio as shown in following Table 1. Herein, results of pH measurement in the reaction system are shown in Table 1. Furthermore, the mixture was stirred under room temperature for the time shown in Table 1, and then analyzed by gas chromatography (GC) to calculate the yield rate. The results are shown in Table 1.

Molecular Weight:174.15
XLogP3:0.4
Hydrogen Bond Acceptor Count:5
Rotatable Bond Count:6
Exact Mass:174.05282342
Monoisotopic Mass:174.05282342
Topological Polar Surface Area:69.7
Heavy Atom Count:12
Complexity:176
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes