甲基 5-(吡咯烷-1-基甲基)呋喃-2-羧酸乙酯

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

实验步骤: A solution of 5-formyl-furan-2-carboxylic acid (2 g, 14.3 mmol) in THF (5 ml) at r.t. was treated with freshly prepared diazomethane in ether (ca. 20 mg/ml) (0.72 ml, 1.2 eq.). The solvent was evaporated and the crude product (1 g, 6.5 mmol) dissolved in THF (10 ml). AcOH (467 mg, 7.8 mmol, 1.2 eq.) and pyrrolidine (554 mg, 7.8 mmol, 1.2 eq.) were added and the mixture stirred at r.t. for 5 hrs. Sodium triacetoxyborohydride (2.06 g, 9.7 mmol, 1.5 eq.) was then added and stirring continued at r.t. under Ar overnight. Satd. NaHCO3 (50 ml) was then added and the mixture extracted with EtOAc, dried with Na2SO4 and the solvent evaporated. The residue was chromatographed over 90 g SiO2 (Merck 230-400 mesh) with EtOAc/n-hexane 1:1 affording the title compound (426 mg, 31% yield) as an orange oil. MS: m/e=209 (M+). The solvent was evaporated stirring continued at r.t. under Ar overnight the mixture extracted with EtOAc dried with Na2SO4 the solvent evaporated