ethyl nitrite

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In a tubular reactor, there was packed 10 ml. of a 0.5 wt.% palladium-on-alumina catalyst (manufactured by Nippon Engerhard Co., Ltd.), followed by introduction of a gaseous mixture consisting of 28.5% by volume of carbon monoxide, 4.5% by volume of hydrogen, 5.7% by volume of ethyl nitrite and 61.3% by volume of nitrogen at a rate of 40.0 l. per hour to subject the gaseous mixture to reaction at a reaction temperature of 120° C. under ambient pressure. According to a gas-chromatographic analysis of the reaction mixture, it was found that ethyl formate was produced in a space time yield of 235 g./l.-catalyst.hr and small amounts of diethyl oxalate and ethanol were by-produced. In a tubular reactor, there was packed per hour to subject the gaseous mixture to reaction at a reaction temperature of 120° C. under ambient pressure was produced in a space time yield of 235 g

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 9.14 g (97.11 mmol) of 4-methylpyrimidine was slowly added to a 0° C. solution of 8.75 g HCl in 40 ml EtOH. To this white suspension was added, over 5 min, 61 ml of a 10-20% by weight solution of ethyl nitrite in EtOH. The reaction was stirred at 0° C. for 10 min and then at RT for 2.5 h. The white salt was filtered and dried under vacuum. The salt was dissolved into 20 ml H2O and very slowly treated with about 200 ml saturated aqueous KHCO3. A white solid precipitated out of the purple solution. The solid was filtered and dried under vacuum to yield the titled compound. To this white suspension was added, over 5 min at RT for 2.5 h The white salt was filtered dried under vacuum The salt was dissolved into 20 ml H2O very slowly treated with about 200 ml saturated aqueous KHCO3 A white solid precipitated out of the purple solution The solid was filtered dried under vacuum

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: It is well-known that during the two-step reaction process of preparing ethylene glycol by synthesis gas, the selection of the CO coupling route of producing oxalate is very important. In view of the practical industrial applications, it is generally thought that the technical route of firstly producing dimethyl oxalate by CO coupling, and then hydrogenating dimethyl oxalate to produce ethylene glycol is the most feasible. However, the CO coupling reaction course needs to consume NO. Therefore, during supplementing the NO raw material to the process of producing dimethyl oxalate by CO coupling, under general situations, methanol, oxygen and NO are used to be subjected to oxidative esterification, and then the nonreactive gases are exhausted by the method of combining compression, condensation and alcohol absorption, and then methyl nitrite resulting from NO reaction is introduced into the system and reacted. However, the encountered problem is that the boiling point (−16.5° C.) of methyl nitrite is rather low, and methyl nitrite is a gas at the normal temperature. Thus, the method of combining compression, condensation and alcohol absorption should be used, resulting in the high costs of operation energy and the poor effects. Nevertheless, in, e.g., one embodiment of the present invention, an oxidative esterification reactor I and the coupling reaction I are introduced into the NO supplementing system, and thereby ethanol, propanol or butanol are firstly subjected to oxidative esterification with oxygen and NO to produce ethyl nitrite, propyl nitrite or butyl nitrite; then the nonreactive inert components introduced into the nitride oxide as the raw material are directly exhausted by simple separation or further treated; then the amount of nitride oxides or nitrous acid esters in the exhausted gases can be restricted to below a comparatively low amount; next, ethyl nitrite (a boiling point of 15° C.), propyl nitrite (a boiling point of 39° C.) or butyl nitrite (a boiling point of 75° C.) and the CO gas I are fed into the coupling reactor Ito be subjected to the coupling reaction so as to produce diethyl oxalate, dipropyl oxalate or dibutyl oxalate; meanwhile, the reaction releases NO; NO from the reaction and unreacted CO and the newly supplemented oxygen and methanol enter the reactor II to produce methyl nitrite; then compression and condensation are no longer required; after separation is carried out by directly using the conventional pressure or temperature, methyl nitrite is mixed with the CO gas II and fed into the coupling reactor II to continue the reaction; NO resulting from the reaction directly enters the entrance of the reactor II for being recycled; the coupling reactor II is the primary reactor of the coupling reaction course, and the coupling reactor I is the reactor of the NO supplementing system performing the assistant function; most of the CO raw materials are reacted through the reactor II to produce dimethyl oxalate. Researchers found that the oxidative esterification of nitride oxides with oxygen and alcohols to produce alkyl nitrite is a quick reaction, while the side reactions of generating nitric acid etc. are slightly slower. The reaction rate of the oxidative esterification course of NO is mainly affected by the resistance of gas-liquid mass transfer. If the gas-liquid mass transfer efficiency is effectively increased, the probability of generating N2O4 can be further effectively reduced, thereby further reducing the losses of nitride oxides or nitrous acid esters. On the basis of the sufficient studies of the features of the oxidative esterification of nitride oxides and oxygen and alcohols, the technical solution of the present invention further proposes the use of the supergravity rotating bed reactor as the reactor of oxidative esterification for fully utilizing the prominent advantage possessed by the supergravity rotating bed reactor which can exponentially increase the gas-liquid mass transfer efficiency and furthermore more effectively promoting the primary reaction and greatly inhibiting the occurrences of side reactions, thereby increasing the utilization efficiencies of the raw materials like NO. In a word, the present invention adequately makes use of the differences of the boiling points of distinct nitrous acid esters and fully utilizes the advantage of the high efficient mass transfer of the supergravity rotating bed reactor, so that the high yield and the high selectivity of the coupling reaction are ensured and meanwhile, the losses of nitride oxides or nitrous acid esters are dramatically reduced, the utilization efficiency of nitride oxides or nitrous acid esters is increased, and the environmental pollution is decreased. to consume NO compression, condensation and alcohol absorption reacted resulting in the high costs of operation energy Nevertheless, in, e.g., one embodiment of the present invention, an oxidative esterification reactor I and the coupling reaction I are introduced into the NO supplementing system

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: It is well-known that during the two-step reaction process of preparing ethylene glycol by synthesis gas, the selection of the CO coupling route of producing oxalate is very important. In view of the practical industrial applications, it is generally thought that the technical route of firstly producing dimethyl oxalate by CO coupling, and then hydrogenating dimethyl oxalate to produce ethylene glycol is the most feasible. However, the CO coupling reaction course needs to consume NO. Therefore, during supplementing the NO raw material to the process of producing dimethyl oxalate by CO coupling, under general situations, methanol, oxygen and NO are used to be subjected to oxidative esterification, and then the nonreactive gases are exhausted by the method of combining compression, condensation and alcohol absorption, and then methyl nitrite resulting from NO reaction is introduced into the system and reacted. However, the encountered problem is that the boiling point (−16.5° C.) of methyl nitrite is rather low, and methyl nitrite is a gas at the normal temperature. Thus, the method of combining compression, condensation and alcohol absorption should be used, resulting in the high costs of operation energy and the poor effects. Nevertheless, in, e.g., one embodiment of the present invention, an oxidative esterification reactor I and the coupling reaction I are introduced into the NO supplementing system, and thereby ethanol, propanol or butanol are firstly subjected to oxidative esterification with oxygen and NO to produce ethyl nitrite, propyl nitrite or butyl nitrite; then the nonreactive inert components introduced into the nitride oxide as the raw material are directly exhausted by simple separation or further treated; then the amount of nitride oxides or nitrous acid esters in the exhausted gases can be restricted to below a comparatively low amount; next, ethyl nitrite (a boiling point of 15° C.), propyl nitrite (a boiling point of 39° C.) or butyl nitrite (a boiling point of 75° C.) and the CO gas I are fed into the coupling reactor Ito be subjected to the coupling reaction so as to produce diethyl oxalate, dipropyl oxalate or dibutyl oxalate; meanwhile, the reaction releases NO; NO from the reaction and unreacted CO and the newly supplemented oxygen and methanol enter the reactor II to produce methyl nitrite; then compression and condensation are no longer required; after separation is carried out by directly using the conventional pressure or temperature, methyl nitrite is mixed with the CO gas II and fed into the coupling reactor II to continue the reaction; NO resulting from the reaction directly enters the entrance of the reactor II for being recycled; the coupling reactor II is the primary reactor of the coupling reaction course, and the coupling reactor I is the reactor of the NO supplementing system performing the assistant function; most of the CO raw materials are reacted through the reactor II to produce dimethyl oxalate. Researchers found that the oxidative esterification of nitride oxides with oxygen and alcohols to produce alkyl nitrite is a quick reaction, while the side reactions of generating nitric acid etc. are slightly slower. The reaction rate of the oxidative esterification course of NO is mainly affected by the resistance of gas-liquid mass transfer. If the gas-liquid mass transfer efficiency is effectively increased, the probability of generating N2O4 can be further effectively reduced, thereby further reducing the losses of nitride oxides or nitrous acid esters. On the basis of the sufficient studies of the features of the oxidative esterification of nitride oxides and oxygen and alcohols, the technical solution of the present invention further proposes the use of the supergravity rotating bed reactor as the reactor of oxidative esterification for fully utilizing the prominent advantage possessed by the supergravity rotating bed reactor which can exponentially increase the gas-liquid mass transfer efficiency and furthermore more effectively promoting the primary reaction and greatly inhibiting the occurrences of side reactions, thereby increasing the utilization efficiencies of the raw materials like NO. In a word, the present invention adequately makes use of the differences of the boiling points of distinct nitrous acid esters and fully utilizes the advantage of the high efficient mass transfer of the supergravity rotating bed reactor, so that the high yield and the high selectivity of the coupling reaction are ensured and meanwhile, the losses of nitride oxides or nitrous acid esters are dramatically reduced, the utilization efficiency of nitride oxides or nitrous acid esters is increased, and the environmental pollution is decreased. to consume NO compression, condensation and alcohol absorption reacted resulting in the high costs of operation energy Nevertheless, in, e.g., one embodiment of the present invention, an oxidative esterification reactor I and the coupling reaction I are introduced into the NO supplementing system

Conditions: temp:-10.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of the product of step (a) (32.2 g) in ethanol (90 ml) cooled to -10° C. was added ethyl nitrite (18 ml) followed by a solution of sodium ethoxide (from sodium (2.65 g) in ethanol (90 ml)), added dropwise over 90 min. The reaction mixture was then stirred at -10° C. for 16 hours evaporated in vacuo and the residue was dissolved in ethanol (150 ml) and acidified to pH 4.0 by the addition of conc. hydrochloric acid. The resulting solution was evaporated in vacuo and the residue treated with a mixture of ether and ethanol (10:1; 150 ml). Sodium chloride was filtered off and the filtrate evaporated in vacuo to give the oxime as a red oil (23.4 g). The n.m.r. spectrum supported the required structure. added dropwise over 90 min evaporated in vacuo the residue was dissolved in ethanol (150 ml) acidified to pH 4.0 by the addition of conc. hydrochloric acid The resulting solution was evaporated in vacuo the residue treated with a mixture of ether and ethanol (10:1; 150 ml) Sodium chloride was filtered off the filtrate evaporated in vacuo

Conditions: temp:-10.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of the product of step (a) (32.2 g) in ethanol (90 ml) cooled to -10° C. was added ethyl nitrite (18 ml) followed by a solution of sodium ethoxide (from sodium (2.65 g) in ethanol (90 ml)), added dropwise over 90 min. The reaction mixture was then stirred at -10° C. for 16 hours evaporated in vacuo and the residue was dissolved in ethanol (150 ml) and acidified to pH 4.0 by the addition of conc. hydrochloric acid. The resulting solution was evaporated in vacuo and the residue treated with a mixture of ether and ethanol (10:1; 150 ml). Sodium chloride was filtered off and the filtrate evaporated in vacuo to give the oxime as a red oil (23.4 g). The n.m.r. spectrum supported the required structure. added dropwise over 90 min evaporated in vacuo the residue was dissolved in ethanol (150 ml) acidified to pH 4.0 by the addition of conc. hydrochloric acid The resulting solution was evaporated in vacuo the residue treated with a mixture of ether and ethanol (10:1; 150 ml) Sodium chloride was filtered off the filtrate evaporated in vacuo

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 4-Methyl-pyrimidine (0.1 M) was added to 100 ml of ethanol containing 3.5 g (0.1 M) of HCl. While keeping the reaction mixture at 5° there was added over 60 minutes a solution of 9 g (0.12 M) of ethyl nitrite in 60 ml of ethyl alcohol, whereupon the whole was kept under stirring for 1 hour at room temperature. The thus formed 4-formyl-pyrimidine-oxime hydrochloride was separated by filtration, dissolved in water and the aqueous solution neutralized by adding Na2CO3. The title compound was finally obtained by filtration and drying. M.p. 154°-155°. Yield 71%. at 5° The thus formed 4-formyl-pyrimidine-oxime hydrochloride was separated by filtration dissolved in water by adding Na2CO3

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 4-Methyl-pyrimidine (0.1 M) was added to 100 ml of ethanol containing 3.5 g (0.1 M) of HCl. While keeping the reaction mixture at 5° there was added over 60 minutes a solution of 9 g (0.12 M) of ethyl nitrite in 60 ml of ethyl alcohol, whereupon the whole was kept under stirring for 1 hour at room temperature. The thus formed 4-formyl-pyrimidine-oxime hydrochloride was separated by filtration, dissolved in water and the aqueous solution neutralized by adding Na2CO3. The title compound was finally obtained by filtration and drying. M.p. 154°-155°. Yield 71%. at 5° The thus formed 4-formyl-pyrimidine-oxime hydrochloride was separated by filtration dissolved in water by adding Na2CO3

Conditions: temp:0.00; pressure:0.00; stir: