2,3-戊二烯二酸,1,5-二甲酯

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

实验步骤: The above-obtained penta-2,3-dienedioic acid dimethyl ester (4.6 g, 30 mmol) and 1-ethoxy-1,3-bis(trimethylsiloxy)hexa-1,3-diene (13 g, 41 mmol) were mixed and stirred at a room temperature for 1.5 hours. The reaction mixture was added with ethanol (100 mL) and ammonium fluoride (5.4 g) and stirred at a room temperature for 2 hours. The reaction mixture was further added with water and extracted with ethyl acetate 3 times. The organic layers were combined, sequentially washed with water and saturated brine, dried over anhydrous sodium sulfate and then the solvent was evaporated under reduced pressure. The residue was triturated with hexane (50 mL) to obtain Compound 23 (3.2 g, 40%). stirred at a room temperature for 2 hours extracted with ethyl acetate 3 times sequentially washed with water and saturated brine dried over anhydrous sodium sulfate the solvent was evaporated under reduced pressure The residue was triturated with hexane (50 mL)

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

实验步骤: The above-obtained penta-2,3-dienedioic acid dimethyl ester (4.6 g, 30 mmol) and 1-ethoxy-1,3-bis(trimethylsiloxy)hexa-1,3-diene (13 g, 41 mmol) were mixed and stirred at a room temperature for 1.5 hours. The reaction mixture was added with ethanol (100 mL) and ammonium fluoride (5.4 g) and stirred at a room temperature for 2 hours. The reaction mixture was further added with water and extracted with ethyl acetate 3 times. The organic layers were combined, sequentially washed with water and saturated brine, dried over anhydrous sodium sulfate and then the solvent was evaporated under reduced pressure. The residue was triturated with hexane (50 mL) to obtain Compound 23 (3.2 g, 40%). stirred at a room temperature for 2 hours extracted with ethyl acetate 3 times sequentially washed with water and saturated brine dried over anhydrous sodium sulfate the solvent was evaporated under reduced pressure The residue was triturated with hexane (50 mL)

反应条件: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 3-Oxopentanedioic acid dimethyl ester (11 mL, 75 mmol) was dissolved in dichloromethane (100 mL), and cooled to 0° C. The obtained solution was added with 2-chloro-1,3-dimethylimidazolium chloride (14 g, 83 mmol) and triethylamine (31 mL, 0.23 mol), warmed up to a room temperature and stirred for 4 hours. The reaction mixture was added with hexane (200 mL) and water and extracted with hexane 3 times. The organic layers were combined and sequentially washed with water and saturated brine, dried over anhydrous sodium sulfate and then evaporated under reduced pressure. The residue was purified by silica gel column chromatography (hexane/ethyl acetate=2/1) to obtain penta-2,3-dienedioic acid dimethyl ester (4.7 g, 40%). warmed up to a room temperature extracted with hexane 3 times sequentially washed with water and saturated brine dried over anhydrous sodium sulfate evaporated under reduced pressure The residue was purified by silica gel column chromatography (hexane/ethyl acetate=2/1)

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

实验步骤: The above-obtained penta-2,3-dienedioic acid dimethyl ester (4.6 g, 30 mmol) and 1-ethoxy-1,3-bis(trimethylsiloxy)hexa-1,3-diene (13 g, 41 mmol) were mixed and stirred at a room temperature for 1.5 hours. The reaction mixture was added with ethanol (100 mL) and ammonium fluoride (5.4 g) and stirred at a room temperature for 2 hours. The reaction mixture was further added with water and extracted with ethyl acetate 3 times. The organic layers were combined, sequentially washed with water and saturated brine, dried over anhydrous sodium sulfate and then the solvent was evaporated under reduced pressure. The residue was triturated with hexane (50 mL) to obtain Compound 23 (3.2 g, 40%). stirred at a room temperature for 2 hours extracted with ethyl acetate 3 times sequentially washed with water and saturated brine dried over anhydrous sodium sulfate the solvent was evaporated under reduced pressure The residue was triturated with hexane (50 mL)

反应条件: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 3-Oxopentanedioic acid dimethyl ester (11 mL, 75 mmol) was dissolved in dichloromethane (100 mL), and cooled to 0° C. The obtained solution was added with 2-chloro-1,3-dimethylimidazolium chloride (14 g, 83 mmol) and triethylamine (31 mL, 0.23 mol), warmed up to a room temperature and stirred for 4 hours. The reaction mixture was added with hexane (200 mL) and water and extracted with hexane 3 times. The organic layers were combined and sequentially washed with water and saturated brine, dried over anhydrous sodium sulfate and then evaporated under reduced pressure. The residue was purified by silica gel column chromatography (hexane/ethyl acetate=2/1) to obtain penta-2,3-dienedioic acid dimethyl ester (4.7 g, 40%). warmed up to a room temperature extracted with hexane 3 times sequentially washed with water and saturated brine dried over anhydrous sodium sulfate evaporated under reduced pressure The residue was purified by silica gel column chromatography (hexane/ethyl acetate=2/1)