3,4-二氢-6-甲基-2H-吡喃-2-酮

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 1.39 g of 5-acetonyl-3-methylisoxazole, 1.68 g of 3,4-dihydro-6-methyl-2H-pyran-2-one and 3.42 g of cecium carbonate were added to 20 ml of acetonitrile to heat at reflux for 3 hours. After returning to room temperatrure, the reaction solution was poured into 100 ml of ice water with hydrochloric acid added, and extracted with ethyl acetate. The organic layer was washed with water and then with saturated salt water, and dried over magnesium sulfate. The solvent was concentrated under reduced pressure. The obtained crude product was purified on silica gel column chromatography to give 2.03 g of the title compound as a colorless viscous liquid. to heat at reflux for 3 hours added extracted with ethyl acetate The organic layer was washed with water with saturated salt water, and dried over magnesium sulfate The solvent was concentrated under reduced pressure The obtained crude product was purified on silica gel column chromatography

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 1.39 g of 5-acetonyl-3-methylisoxazole, 1.68 g of 3,4-dihydro-6-methyl-2H-pyran-2-one and 3.42 g of cecium carbonate were added to 20 ml of acetonitrile to heat at reflux for 3 hours. After returning to room temperatrure, the reaction solution was poured into 100 ml of ice water with hydrochloric acid added, and extracted with ethyl acetate. The organic layer was washed with water and then with saturated salt water, and dried over magnesium sulfate. The solvent was concentrated under reduced pressure. The obtained crude product was purified on silica gel column chromatography to give 2.03 g of the title compound as a colorless viscous liquid. to heat at reflux for 3 hours added extracted with ethyl acetate The organic layer was washed with water with saturated salt water, and dried over magnesium sulfate The solvent was concentrated under reduced pressure The obtained crude product was purified on silica gel column chromatography

反应条件: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 4.75 g of TMEDA was dissolved in 10 ml of THF, and 3.3 g of 3,5-dimethylisoxazole was added. The resulting solution was cooled to −78° C. in a dry ice-acetone bath, and 26 ml of an n-hexane solution of n-butyl lithium (1.6M solution) was dropped into it. They were reacted at the same temperature for 30 minutes, and then, at −78° C., a solution of 1.90 g of 3,4-dihydro-6-methyl-2H-pyran-2-one and 5 ml of DMSO in 10 ml of THF was dropped. The resulting solution was stirred at the same temperature for 2 hours. The dry ice-acetone bath was taken away. After gradually returning to room temperature, the solution was stirred for 15 hours. The reaction solution was poured into dilute hydrochloric acid-ice and extracted with ethyl acetate. The organic layer was washed with water and then with saturated salt water, and dried over anhydrous magnesium sulfate. The solvent was concentrated under reduced pressure. The obtained residue was purified on silica gel column chromatography to give 1.10 g of the title compound as white crystals. Melting point: 104-105° C. They were reacted at the same temperature for 30 minutes After gradually returning to room temperature the solution was stirred for 15 hours extracted with ethyl acetate The organic layer was washed with water with saturated salt water, and dried over anhydrous magnesium sulfate The solvent was concentrated under reduced pressure The obtained residue was purified on silica gel column chromatography

反应条件: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 4.75 g of TMEDA was dissolved in 10 ml of THF, and 3.3 g of 3,5-dimethylisoxazole was added. The resulting solution was cooled to −78° C. in a dry ice-acetone bath, and 26 ml of an n-hexane solution of n-butyl lithium (1.6M solution) was dropped into it. They were reacted at the same temperature for 30 minutes, and then, at −78° C., a solution of 1.90 g of 3,4-dihydro-6-methyl-2H-pyran-2-one and 5 ml of DMSO in 10 ml of THF was dropped. The resulting solution was stirred at the same temperature for 2 hours. The dry ice-acetone bath was taken away. After gradually returning to room temperature, the solution was stirred for 15 hours. The reaction solution was poured into dilute hydrochloric acid-ice and extracted with ethyl acetate. The organic layer was washed with water and then with saturated salt water, and dried over anhydrous magnesium sulfate. The solvent was concentrated under reduced pressure. The obtained residue was purified on silica gel column chromatography to give 1.10 g of the title compound as white crystals. Melting point: 104-105° C. They were reacted at the same temperature for 30 minutes After gradually returning to room temperature the solution was stirred for 15 hours extracted with ethyl acetate The organic layer was washed with water with saturated salt water, and dried over anhydrous magnesium sulfate The solvent was concentrated under reduced pressure The obtained residue was purified on silica gel column chromatography

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 1.39 g of 5-acetonyl-3-methylisoxazole, 1.68 g of 3,4-dihydro-6-methyl-2H-pyran-2-one and 3.42 g of cecium carbonate were added to 20 ml of acetonitrile to heat at reflux for 3 hours. After returning to room temperatrure, the reaction solution was poured into 100 ml of ice water with hydrochloric acid added, and extracted with ethyl acetate. The organic layer was washed with water and then with saturated salt water, and dried over magnesium sulfate. The solvent was concentrated under reduced pressure. The obtained crude product was purified on silica gel column chromatography to give 2.03 g of the title compound as a colorless viscous liquid. to heat at reflux for 3 hours added extracted with ethyl acetate The organic layer was washed with water with saturated salt water, and dried over magnesium sulfate The solvent was concentrated under reduced pressure The obtained crude product was purified on silica gel column chromatography

反应条件: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 4.75 g of TMEDA was dissolved in 10 ml of THF, and 3.3 g of 3,5-dimethylisoxazole was added. The resulting solution was cooled to −78° C. in a dry ice-acetone bath, and 26 ml of an n-hexane solution of n-butyl lithium (1.6M solution) was dropped into it. They were reacted at the same temperature for 30 minutes, and then, at −78° C., a solution of 1.90 g of 3,4-dihydro-6-methyl-2H-pyran-2-one and 5 ml of DMSO in 10 ml of THF was dropped. The resulting solution was stirred at the same temperature for 2 hours. The dry ice-acetone bath was taken away. After gradually returning to room temperature, the solution was stirred for 15 hours. The reaction solution was poured into dilute hydrochloric acid-ice and extracted with ethyl acetate. The organic layer was washed with water and then with saturated salt water, and dried over anhydrous magnesium sulfate. The solvent was concentrated under reduced pressure. The obtained residue was purified on silica gel column chromatography to give 1.10 g of the title compound as white crystals. Melting point: 104-105° C. They were reacted at the same temperature for 30 minutes After gradually returning to room temperature the solution was stirred for 15 hours extracted with ethyl acetate The organic layer was washed with water with saturated salt water, and dried over anhydrous magnesium sulfate The solvent was concentrated under reduced pressure The obtained residue was purified on silica gel column chromatography

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 1.39 g of 5-acetonyl-3-methylisoxazole, 1.68 g of 3,4-dihydro-6-methyl-2H-pyran-2-one and 3.42 g of cecium carbonate were added to 20 ml of acetonitrile to heat at reflux for 3 hours. After returning to room temperatrure, the reaction solution was poured into 100 ml of ice water with hydrochloric acid added, and extracted with ethyl acetate. The organic layer was washed with water and then with saturated salt water, and dried over magnesium sulfate. The solvent was concentrated under reduced pressure. The obtained crude product was purified on silica gel column chromatography to give 2.03 g of the title compound as a colorless viscous liquid. to heat at reflux for 3 hours added extracted with ethyl acetate The organic layer was washed with water with saturated salt water, and dried over magnesium sulfate The solvent was concentrated under reduced pressure The obtained crude product was purified on silica gel column chromatography

反应条件: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 4.75 g of TMEDA was dissolved in 10 ml of THF, and 3.3 g of 3,5-dimethylisoxazole was added. The resulting solution was cooled to −78° C. in a dry ice-acetone bath, and 26 ml of an n-hexane solution of n-butyl lithium (1.6M solution) was dropped into it. They were reacted at the same temperature for 30 minutes, and then, at −78° C., a solution of 1.90 g of 3,4-dihydro-6-methyl-2H-pyran-2-one and 5 ml of DMSO in 10 ml of THF was dropped. The resulting solution was stirred at the same temperature for 2 hours. The dry ice-acetone bath was taken away. After gradually returning to room temperature, the solution was stirred for 15 hours. The reaction solution was poured into dilute hydrochloric acid-ice and extracted with ethyl acetate. The organic layer was washed with water and then with saturated salt water, and dried over anhydrous magnesium sulfate. The solvent was concentrated under reduced pressure. The obtained residue was purified on silica gel column chromatography to give 1.10 g of the title compound as white crystals. Melting point: 104-105° C. They were reacted at the same temperature for 30 minutes After gradually returning to room temperature the solution was stirred for 15 hours extracted with ethyl acetate The organic layer was washed with water with saturated salt water, and dried over anhydrous magnesium sulfate The solvent was concentrated under reduced pressure The obtained residue was purified on silica gel column chromatography