反应详情

Sodium hydride (50% w/w dispersion in mineral oil, 55 mg) was added under argon to a stirred solution of the product from step (iii) above (300 mg) in dry DMF (5 ml). After five minutes, ethyl 6-bromohexanoate (0.20 ml) was added and the mixture stirred for 16 hours. The DMF was evaporated in vacuo and the residue partitioned between dichloromethane and water. The aqueous phase was extracted with further dichloromethane. The combined organic extracts were washed with water then dried, and evaporated. The residue was purified by chromatography on alumina, eluting with dichloromethane and then 1% v/v methanol/dichloromethane. Evaporation of the appropriate fractions gave ethyl 6-[4-[N-(4-pyridyl)-N-tertiary-butyloxycarbonylamino]phenoxy]hexanoate, 260 mg, as a yellow gum: NMR (CDCl3) δ8.40 (2H, dd), 7.16 (2H, dd), 7.07 (2H, m), 6.90 (2H, m), 4.13 (2H, q), 3.98 (2H, t), 2.34 (2H, t), 1.78 (4H, m), 1.57 (2H, m); 1.44 (9H, s), 1.26 (3H, t); m/e 429 (M+H)+.

1. customThe DMF was evaporated in vacuo
2. customthe residue partitioned between dichloromethane and water
3. extractionThe aqueous phase was extracted with further dichloromethane
4. washThe combined organic extracts were washed with water
5. customthen dried
6. customevaporated
7. customThe residue was purified by chromatography on alumina
8. washeluting with dichloromethane
9. customEvaporation of the appropriate fractions