반응 #1532947

반응 방정식

1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone

n-BuLi

1,3-dithiane

2-(4-bromo-phenyl)-4-(2-iodo-ethyl)-5-methyl-oxazole

Intermediate 30

2-(4-bromo-phenyl)-4-(2-iodo-ethyl)-5-methyl-oxazole

dithiane

→

2-(4-bromo-phenyl)-4-(2-[1,3]dithian-2-yl-ethyl)-5-methyl-oxazole

수율 66.0%

용매

THF

THF

water

반응 조건

후처리

1. 1
   기타Preparation
2. 2
   workup.STIRRING] Stir the reaction mixture at −78° C. for 15 min
3. 3
   기타Add dichloromethane, and separate the layers
4. 4
   건조Dry the crude organic extracts over MgSO4
5. 5
   여과filter
6. 6
   농축concentrate
7. 7
   기타Purify on silica gel 0-10% EtOAc/Hexanes

실험 절차

Add a cold (−78° C.) solution of 2-(4-bromo-phenyl)-4-(2-iodo-ethyl)-5-methyl-oxazole (See Intermediate 30) (1.05 g, 2.67 mmol) in 15 mL THF to a cold (−78° C.) solution of dithiane anion [Preparation: Add n-BuLi (7.5 mL, 12 mmol, 1.6M in hexanes) to a −20° C. solution of 1,3-dithiane (1.92 g, 15.9 mmol) in 25 mL THF. Stir 20 min at −78° C. and add 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (DMPU, 4.03 g, 31.4 mmol).] Stir the reaction mixture at −78° C. for 15 min. Add water and warm to room temperature. Add dichloromethane, and separate the layers. Dry the crude organic extracts over MgSO4, filter and concentrate. Purify on silica gel 0-10% EtOAc/Hexanes to give 2-(4-bromo-phenyl)-4-(2-[1,3]dithian-2-yl-ethyl)-5-methyl-oxazole (0.672 g, 66%). MS (m/e): 384 (M+1).

출처