巴豆酸异丙酯

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

实验步骤: Crotonic acid (193.7 g, 2.25 mol) was dissolved in 2-propanol (860 mL, 11.25 mol) in a 2 L flask and then well stirred, after which sulfuric acid (24 mL, 0.45 mol) was slowly added in droplets to the mixture and refluxed and stirred for 48 hours or longer. The stirred mixture was cooled to room temperature, after which the obtained mixture was washed with distilled water (1000 mL), and the organic layer was separated, neutralized and subjected to atmospheric distillation (80° C.), thus obtaining 220 g (1.71 mol, yield 76.3%) of crotonic acid isopropyl ester. refluxed stirred for 48 hours or longer after which the obtained mixture was washed with distilled water (1000 mL) the organic layer was separated subjected to atmospheric distillation (80° C.)

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

实验步骤: 40.0 g (465 mmol) of crotonic acid (Fluka 28010), 25.1 g (418 mmol) of isopropanol (Merck 1.09634.2500), 200 mL of benzene, 4.2 g of conc. H2SO4 and 2.1 g of para-toluene sulfonic acid was charged to a 500 mL flask equipped with a magnetic stirrer bar and Dean-Stark water separator. The mixture was refluxed until water formation ceased. 200 mL of ether was added to the mixture, and then washed with several portions of NaHCO3 (aq., sat.) until the the acid was neutralized. Organic phase was separated, dried with MgSO4 and filtered. Solvent was removed under reduced pressure and the remainder distilled at 95° C. to give 30.5 g of isopropylcrotonate. Yield 57%. 1H-NMR (CDCl3): 6.95 (dq, 1H), 5.82 (d, 1H), 5.05 (sept, 1H), 1.88 (d, 3H), 1.25 (d, 6H). equipped with a magnetic stirrer bar washed with several portions of NaHCO3 (aq., sat.) until the the acid Organic phase was separated dried with MgSO4 filtered Solvent was removed under reduced pressure the remainder distilled at 95° C.

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

实验步骤: Crotonic acid (193.7 g, 2.25 mol) was dissolved in 2-propanol (860 mL, 11.25 mol) in a 2 L flask and then well stirred, after which sulfuric acid (24 mL, 0.45 mol) was slowly added in droplets to the mixture and refluxed and stirred for 48 hours or longer. The stirred mixture was cooled to room temperature, after which the obtained mixture was washed with distilled water (1000 mL), and the organic layer was separated, neutralized and subjected to atmospheric distillation (80° C.), thus obtaining 220 g (1.71 mol, yield 76.3%) of crotonic acid isopropyl ester. refluxed stirred for 48 hours or longer after which the obtained mixture was washed with distilled water (1000 mL) the organic layer was separated subjected to atmospheric distillation (80° C.)