反应详情

A solution of 1N ZnCl2 in Et2O (60.7 mL, 60.7 mmol) was added dropwise over 15 min to a solution of 4-(hydroxymethyl)-1-piperidinecarbonitrile (7.09 g, 50.6 mmol) and N-hydroxy-2-methylpropanimidamide (6.2 g, 60.7 mmol) in EtOAc (150 mL) at ambient temperature. The reaction mixture was left at ambient temperature for 15 min, decanted, and triturated with Et2O to give a white solid. The solid was heated in a solution of concentrated HCl (15 mL) and ethanol (30 mL) for 1 h. Ethanol was removed in vacuo, and the resulting residue was charged with water (150 mL). The mixture was neutralized with Na2CO3, and extracted with CH2Cl2. The organic extracts were dried over MgSO4, filtered, and the filtrate was concentrated. The crude product was purified by chromatography on a silica gel column using 0 to 100% EtOAc/hexane to give 4.44 g (39%) of {1-[3-(1-methylethyl)-1,2,4-oxadiazol-5-yl]-4-piperidinyl}methanol as a clear oil. 1H NMR (400 MHz, CDCl3): δ 4.20-4.10 (m, 2H), 3.51 (d, 2H, J=6.4 Hz), 3.07-2.97 (m, 2H), 2.90-2.75 (m, 1H), 1.85-1.75 (m, 2H), 1.76-1.62 (m, 1H), 1.36-1.19 (m, 8H); LRMS (ESI), m/z 226 (M+H).

1. customdecanted
2. customtriturated with Et2O
3. customto give a white solid
4. customEthanol was removed in vacuo
5. additionthe resulting residue was charged with water (150 mL)
6. extractionextracted with CH2Cl2
7. dry with materialThe organic extracts were dried over MgSO4
8. filtrationfiltered
9. concentrationthe filtrate was concentrated
10. customThe crude product was purified by chromatography on a silica gel column