反应详情

4-amino-2,6-diethylpyridine (D) (1.8 g) was added to a solution of iodine (3.1 g) and [bis(trifluoroacetoxy)iodo]benzene (5.7 g) in a mixture of dichloromethane (70 ml) and methanol (20 ml) and the mixture was stirred for 16 hours. Solvent was removed by evaporation and the residue was partitioned between ethyl acetate and a mixture of saturated sodium metabisulphite solution (50 ml) and saturated sodium carbonate solution (150 ml). The organic phase was separated, washed with saturated sodium chloride solution and dried (MgSO4). Solvent was removed by evaporation with the residue was purified by flash chromatography eluting with dichloromethane/methanol (97:3 v/v) to give 4-amino-2,6-diethyl-3-iodopyridine (E) (1.33 g) as a solid, m.p. 72°-74° C.; NMR (CDCl3): 1.25(m,6H), 2.65(q,2H), 2.96(q,2H), 4.59(broad s,2H), 6.30(s,1H); mass spectrum (chemical ionisation, ammonia): 277(M+H)+.

1. customSolvent was removed by evaporation
2. customthe residue was partitioned between ethyl acetate
3. additiona mixture of saturated sodium metabisulphite solution (50 ml) and saturated sodium carbonate solution (150 ml)
4. customThe organic phase was separated
5. washwashed with saturated sodium chloride solution
6. dry with materialdried (MgSO4)
7. customSolvent was removed by evaporation with the residue
8. customwas purified by flash chromatography
9. washeluting with dichloromethane/methanol (97:3 v/v)