反应详情

Add a solution of commercially available 5-phenylethynyl-nicotinic acid ethyl ester (0.4 g, 1.59 mmol) in dry tetrahydrofuran (20 mL) to a solution of lithium aluminum hydride (20 mL, 0.08 M in tetrahydrofuran) at room temperature under nitrogen and stir for 3 h. Add a solution of lithium aluminum hydride (2 mL, 1 M in tetrahydrofuran) and stir for 1 h. Slowly add methanol (2 mL) and concentrate. Dilute with ethyl acetate, wash with water and a saturated aqueous solution of sodium chloride and dry. Purify the residue by silica gel chromatography, eluting with 5:1 hexanes:ethyl acetate to 10:90 hexanes:ethyl acetate, to give the E-isomer (7 mg, 2%).

1. stirringstir for 1 h
2. concentrationSlowly add methanol (2 mL) and concentrate
3. additionDilute with ethyl acetate
4. washwash with water
5. dry with materiala saturated aqueous solution of sodium chloride and dry
6. customPurify the residue by silica gel chromatography
7. washeluting with 5:1 hexanes
8. customethyl acetate to 10:90 hexanes:ethyl acetate, to give the E-isomer (7 mg, 2%)