反应详情

A mixture of 1-methyl-4-imidazolin-2-one (4 gms, 0.04 mol), 20 ml of formaldehyde (37% aqueous solution), sodium hydroxide (100 mg), and 20 ml of methanol was stirred at room temperature for 20 hours. After removing the solvent using a rotovap at reduced pressure, a liquid residue was obtained and filtered through a column of silica gel using chloroform as the eluent. The residue solidified after left standing overnight and was dissolved in water and then extracted with chloroform. The aqueous phase was concentrated and chromatographed through a column of silica gel G 60. Removal of the solvent afforded a solid which upon addition of acetone became white suspension. The solid was washed twice with acetone and air-dried (1.0 gm, 22%) and sublimed at reduced pressure, m.p. 101.5°-103.5° C. Found: C, 46.70; H, 6.18: N, 21.80. Calc. for C5H8N2O2 : C, 46.87; H, 6.29; N, 21.86%. 1H n.m.r.(CDCl3 ): δ3.15(3H, s, CH3N--); 5.02(2H, s, broad, N-CH2OH); 5.8(1H, s, broad, OH); 6.1 (1H, d, J=3 Hz, HC-CH); 6.3(1H, d, J=3 Hz, HC=CH). νmax (KBr): 3220(OH, broad); 3120, 3100(HC=CH); 1655 cm-1 (C=O). m/e 128, C5H8N2O2 requires 128.

1. customAfter removing the solvent
2. customa liquid residue was obtained
3. filtrationfiltered through a column of silica gel
4. waitafter left standing overnight
5. dissolutionwas dissolved in water
6. extractionextracted with chloroform
7. concentrationThe aqueous phase was concentrated
8. customchromatographed through a column of silica gel G 60
9. customRemoval of the solvent
10. customafforded a solid which
11. washThe solid was washed twice with acetone
12. customair-dried (1.0 gm, 22%)