O[CH2:2][C:3]1[N:8]=[C:7](/[CH:9]=[CH:10]/[C:11]([O:13][C:14]([CH3:17])([CH3:16])[CH3:15])=[O:12])[CH:6]=[CH:5][CH:4]=1.C(Br)(Br)(Br)[Br:19].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>C(Cl)Cl.C(Cl)(Cl)Cl>[Br:19][CH2:2][C:3]1[N:8]=[C:7](/[CH:9]=[CH:10]/[C:11]([O:13][C:14]([CH3:17])([CH3:16])[CH3:15])=[O:12])[CH:6]=[CH:5][CH:4]=1To a solution prepared with t-butyl 3-(6-hydroxymethyl-pyridin-2-yl)-trans-acrylate (trans form, 2 g) described in Reference Example 10-(1) and carbon tetrabromide (4.23 g) in methylene chloride (20 mL) at ice temperature, triphenylphosphine (2.68 g) was added in small portions, and the mixture was stirred at the same temperature for 15 minutes. The reaction solution was transferred to a separating funnel, diluted with chloroform, washed with saturated aqueous sodium bicarbonate and brine, dried over anhydrous magnesium sulfate, and then concentrated under reduced pressure. The residue was purified by chromatography on silica gel (hexane-ethyl acetate=10:1) to give 2.23 g of t-butyl 3-(6-bromomethylpyridin-2-yl)-trans-acrylate as a light yellow powder.
Wird geladen…
