A kind of n, n-dimethyltetrahydrofurfurylamine synthetic method

Abstract

The invention relates to organic compound synthesis methods, in particular to an N,N-dimethyl tetrahydrofurfuryl amine synthesis method. The method includes steps: 1) mixing reactants with N,N-dimethyl formamide or N,N-dimethylacetamide and formic acid in a reaction vessel, and performing heating reaction; 1) after heating reaction is finished, performing distillation recovery of DMF (dimethyl formamide) or DMAC (dimethylacetamide) and the formic acid, and subjecting residues to vacuum distillation to obtain N,N-dimethyl furfuryl amine which is an intermediate product; 3) subjecting the intermediate product N,N-dimethyl furfuryl amine to catalytic hydrogenation, and distilling to obtain a product of N,N-dimethyl tetrahydrofurfuryl amine. The N,N-dimethyl tetrahydrofurfuryl amine synthesis method has advantages that raw materials are cheap and extensive in source; problems of low furfural yield and difficulty in separation due to instability of furfural acids are avoided, and acidity and reducibility of the formic acid are fully used; high hydrogenation selectivity and catalyst recyclability are realized; mild conditions, easiness in implementation and high raw material utilization rate are realized, and excessive formic acid and N,N-dimethyl formamide or N,N-dimethylacetamide are easy to recover.

Description

technical field

[0001] The invention relates to a method for synthesizing organic compounds, in particular to a method for synthesizing N,N-dimethyltetrahydrofurfurylamine. Background technique

[0002] N,N-Dimethyltetrahydrofurfurylamine is an asymmetric structure regulator, which can be widely used in the synthesis of polybutadiene rubber, and can precisely control the microstructure of butadiene homopolymers and copolymers. Chinese patent CN 101845109 B reports in detail the structural characteristics of N-alkyltetrahydrofurfurylamine compound asymmetric regulators and their use in controlling butadiene homopolymerization and butadiene / styrene copolymer butadiene 1, 2 Structure Microstructure. Chinese patent CN 103508986 B reports a synthesis method of N,N-dimethyltetrahydrofurfurylamine. This method utilizes furfural and dimethylamine aqueous solution as raw materials, uses Raney nickel as a catalyst, and uses one-pot catalytic hydrogenation to produce have to. This m...

Examples

Embodiment 1

[0020] Add 50g of crushed corncobs, 400g of N,N-dimethylformamide (DMF) and 200g of formic acid into a 1000mL round-bottomed flask, place the flask in an oil bath to stir and heat for reaction, the temperature is 135°C, and the reaction time for 10h. After the reaction was completed, the residue was filtered out, the filtrate was distilled to recover formic acid and DMF, and the residue was distilled under reduced pressure at 52.5-64°C and 2000 Pa to obtain 11.5 g of N,N-dimethylfurfurylamine product. Then add 11.5g of N,N-dimethylfurfurylamine product and 200mL of methanol into a 400mL autoclave, then add 0.2g of catalyst Raney nickel, feed 5.0MPa hydrogen to heat the reaction, the temperature is 180°C, and the reaction time is After 3 hours, the reaction was distilled under atmospheric pressure, the solvent was recovered, and 11.2 g of the N,N-dimethyltetrahydrofurfurylamine product was collected at 155-162 ° C. The product separation mass yield (based on corn cobs) was 22.4...

Embodiment 2

[0022] Add 50g of xylose, 250g of N,N-dimethylformamide (DMF) and 60g of formic acid into a 500mL round-bottomed flask, place the flask in an oil bath, stir and heat for reaction, the temperature is 130°C, and the reaction time is 8h. After the reaction, the residue was filtered out, the filtrate was distilled to recover formic acid and DMF, and the residue was distilled under reduced pressure at 52.5-64°C and 2000 Pa to obtain 32.7g of N,N-dimethylfurfurylamine product with a molar yield of 76%. Then add 32.7g of N,N-dimethylfurfurylamine product and 200mL of methanol into a 400mL autoclave, then add 1.5g of catalyst Raney nickel, feed 10.0MPa hydrogen to heat and react, the temperature is 150°C, and the reaction time is 4h, atmospheric pressure distillation after reaction finishes, reclaims solvent, collects 155~162 ℃ cut N, N-dimethyltetrahydrofurfurylamine product 31.4g, hydrogenation molar yield is 92%, product total molar yield (based on wood sugar) was 69.9%.

Embodiment 3

[0024] Add 50g of furfural, 250g of N,N-dimethylformamide (DMF) and 35g of formic acid into a 500mL round-bottomed flask, place the flask in an oil bath, stir and heat for reaction, the temperature is 130°C, and the reaction time is 10h. After the reaction was completed, the residue was filtered out, the filtrate was distilled to recover formic acid and DMF, and the residue was distilled under reduced pressure at 52.5-64 ° C and 2000 Pa to obtain 56.7 g of N, N-dimethylfurfurylamine product with a molar yield of 86%. Then add 56.7g of N,N-dimethylfurfurylamine product and 200mL of ethanol into a 400mL autoclave, then add 0.2g of catalyst Pd / C, feed 3.0MPa hydrogen to heat the reaction, the temperature is 150°C, and the reaction time is 5h, atmospheric pressure distillation after reaction finishes, reclaims solvent, collects 155~162 ℃ cut N, N-dimethyltetrahydrofurfurylamine product 55.6g, hydrogenation molar yield is 95%, product total molar yield (based on wood sugar) was 81....

technical field

[0001] The invention relates to a method for synthesizing organic compounds, in particular to a method for synthesizing N,N-dimethyltetrahydrofurfurylamine. Background technique

[0002] N,N-Dimethyltetrahydrofurfurylamine is an asymmetric structure regulator, which can be widely used in the synthesis of polybutadiene rubber, and can precisely control the microstructure of butadiene homopolymers and copolymers. Chinese patent CN 101845109 B reports in detail the structural characteristics of N-alkyltetrahydrofurfurylamine compound asymmetric regulators and their use in controlling butadiene homopolymerization and butadiene / styrene copolymer butadiene 1, 2 Structure Microstructure. Chinese patent CN 103508986 B reports a synthesis method of N,N-dimethyltetrahydrofurfurylamine. This method utilizes furfural and dimethylamine aqueous solution as raw materials, uses Raney nickel as a catalyst, and uses one-pot catalytic hydrogenation to produce have to. This m...

Examples

Embodiment 1

[0020] Add 50g of crushed corncobs, 400g of N,N-dimethylformamide (DMF) and 200g of formic acid into a 1000mL round-bottomed flask, place the flask in an oil bath to stir and heat for reaction, the temperature is 135°C, and the reaction time for 10h. After the reaction was completed, the residue was filtered out, the filtrate was distilled to recover formic acid and DMF, and the residue was distilled under reduced pressure at 52.5-64°C and 2000 Pa to obtain 11.5 g of N,N-dimethylfurfurylamine product. Then add 11.5g of N,N-dimethylfurfurylamine product and 200mL of methanol into a 400mL autoclave, then add 0.2g of catalyst Raney nickel, feed 5.0MPa hydrogen to heat the reaction, the temperature is 180°C, and the reaction time is After 3 hours, the reaction was distilled under atmospheric pressure, the solvent was recovered, and 11.2 g of the N,N-dimethyltetrahydrofurfurylamine product was collected at 155-162 ° C. The product separation mass yield (based on corn cobs) was 22.4...

Embodiment 2

[0022] Add 50g of xylose, 250g of N,N-dimethylformamide (DMF) and 60g of formic acid into a 500mL round-bottomed flask, place the flask in an oil bath, stir and heat for reaction, the temperature is 130°C, and the reaction time is 8h. After the reaction, the residue was filtered out, the filtrate was distilled to recover formic acid and DMF, and the residue was distilled under reduced pressure at 52.5-64°C and 2000 Pa to obtain 32.7g of N,N-dimethylfurfurylamine product with a molar yield of 76%. Then add 32.7g of N,N-dimethylfurfurylamine product and 200mL of methanol into a 400mL autoclave, then add 1.5g of catalyst Raney nickel, feed 10.0MPa hydrogen to heat and react, the temperature is 150°C, and the reaction time is 4h, atmospheric pressure distillation after reaction finishes, reclaims solvent, collects 155~162 ℃ cut N, N-dimethyltetrahydrofurfurylamine product 31.4g, hydrogenation molar yield is 92%, product total molar yield (based on wood sugar) was 69.9%.

Embodiment 3

[0024] Add 50g of furfural, 250g of N,N-dimethylformamide (DMF) and 35g of formic acid into a 500mL round-bottomed flask, place the flask in an oil bath, stir and heat for reaction, the temperature is 130°C, and the reaction time is 10h. After the reaction was completed, the residue was filtered out, the filtrate was distilled to recover formic acid and DMF, and the residue was distilled under reduced pressure at 52.5-64 ° C and 2000 Pa to obtain 56.7 g of N, N-dimethylfurfurylamine product with a molar yield of 86%. Then add 56.7g of N,N-dimethylfurfurylamine product and 200mL of ethanol into a 400mL autoclave, then add 0.2g of catalyst Pd / C, feed 3.0MPa hydrogen to heat the reaction, the temperature is 150°C, and the reaction time is 5h, atmospheric pressure distillation after reaction finishes, reclaims solvent, collects 155~162 ℃ cut N, N-dimethyltetrahydrofurfurylamine product 55.6g, hydrogenation molar yield is 95%, product total molar yield (based on wood sugar) was 81....

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