90% |
With methanol; sodium tetrahydroborate at 0 - 20℃; for 2h; |
At 0 °C, a solution of 1 -(oxazol-2-yl)ethanone (1.0 g, 9.00 mmol, J&W Pharmlab) in MeOH (40 mL) was treated with sodium borohydride (0.39 g, 10.31 mmol) in 2 portions. After 15 min the reaction was allowed to warm to RT for 2 h. The reaction was quenched with water (5 mL). The mixture was partitioned between brine/DCM and the aqueous layer was extracted with DCM (2 x). The combined organic layers were washed brine, dried over Na2SO4 and concentrated under reduced pressure to give 920 mg (90%) of a light-yellow oil. 1H NMR (300 MHz, CDCl3) δ ppm 7.62 (d, J=0.88 Hz, 1 H), 7.07 (s, 1 H), 4.97 (q, J=6.58 Hz, 1 H), 1.62 (d, J=6.72 Hz, 3 H). LC/MS (ESI+) m/z = 114.1 (M+H)+ |
43.2% |
With sodium tetrahydroborate In methanol at 20℃; for 3h; |
1-(oxazol-2-yl)ethanol
To a solution of 1-(Oxazol-2-yl)ethanone (0.5 g, 4.50 mmol) in MeOH (10 mL) atroom temperature was added sodium borohydride (0.255 g, 6.75 mmol). The reaction wasstirred at room termperature for 3h. Then it was rotavap to remove the solvent. Theresidue was diluted with EtOAc and saturated NH4C1. Organic was separated and washed with brine, dried over MgSO4, filtered and concentrated to give 1-(oxazol-2-yl)ethanol (0.22 g, 1.945 mmol, 43.2% yield). ‘HNMR(400IVIHz, DMSO-d6) ö 8.03 (d, J=0.9 Hz, 1H), 7.14 (d, J=0.9 Hz, 1H), 5.64 (d, J=5.6 Hz, 1H), 4.77 (qd, J=6.6, 5.6 Hz, 1H), 1.42 (d, J=6.6 Hz, 3H) |
|
With sodium tetrahydroborate In methanol at 0 - 25℃; Inert atmosphere; |
In a flame dried round-bottomed flask equipped with a magnetic stir bar and under inert atmosphere (N2), 1 -oxazol-2-yl-ethanone (446 mg, 4.01 mmol) was dissolved in MeOH (8.0 mL). NaBH4 (206 mg, 5.22 mmol) was added portionwise at 0 0C and the reaction mixture stirred at rt for 30 min. Water (16 mL) was added and the mixture extracted with EA (3 x 20 mL). The combined org. extracts were dried over MgSO4, filtered, and the solvents were removed under reduced pressure to give the title compound as a colorless oil. LC-MS-conditions 02: tR = 0.33 min. |