反应详情

4-Amino-2,6-diethylpyridine (1.8 g) is 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 is stirred for 16 hours. Solvent is removed by evaporation and the residue is partitioned between ethyl acetate and a mixture of saturated sodium metabisulphite solution (50 ml) and saturated sodium carbonate solution (150 ml). The organic phase is separated, washed with saturated sodium chloride solution and dried. Solvent is removed by evaporation and the residue is purified by flash chromatography eluting with dichloromethane/methanol (97:3 v/v) to give 4-amino-2,6-diethyl-3-iodopyridine (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 is removed by evaporation
2. customthe residue is 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 is separated
5. washwashed with saturated sodium chloride solution
6. customdried
7. customSolvent is removed by evaporation
8. customthe residue is purified by flash chromatography
9. washeluting with dichloromethane/methanol (97:3 v/v)