反应详情

A solution of methyl 3-(4-hydroxyphenyl)propionate (10.0 g, 55. 5 mmol), N-methyl-N-dodecylethanolamine (13.5 g, 55.5 mmol) and triphenylphosphine (16.0 g, 61.0 mmol) in dry tetrahydrofuran (200 ml) was treated at 22° C. with diisopropyl azodicarboxylate (12.3 g, 61.0 mmol) added dropwise over 50 min. After 3 h at 22° C., the reaction mixture was evaporated under reduced pressure and the residue was triturated with hexane. The solid formed was filtered, washed with hexane and the combined filtrate was chromatographed on silica gel using a gradient of ethyl acetate in hexane (20%-60%) as eluent. Distillation under vacuum then gave 18.0 g (75%) of 3-{4-[2-(N-dodecyl-N-methylamino)ethoxy]phenyl} propanoic acid, methyl ester as a clear oil: b.p. 180-183° C./0.02 torr (bulb to bulb distillation, air bath temperature).

1. additionadded dropwise over 50 min
2. customthe reaction mixture was evaporated under reduced pressure
3. customthe residue was triturated with hexane
4. customThe solid formed
5. filtrationwas filtered
6. washwashed with hexane
7. customthe combined filtrate was chromatographed on silica gel using a gradient of ethyl acetate in hexane (20%-60%) as eluent
8. distillationDistillation under vacuum