1,2-Dibromoethane → 8-(2-Bromoethoxy)-3,4-dihydro-2H-1-benzothiopyran
Reaction equation
[S:1]1[C:10]2[C:5](=[CH:6][CH:7]=[CH:8][C:9]=2[OH:11])[CH2:4][CH2:3][CH2:2]1.[Br:12][CH2:13][CH2:14]Br.[OH-].[Na+]>>[Br:12][CH2:13][CH2:14][O:11][C:9]1[CH:8]=[CH:7][CH:6]=[C:5]2[C:10]=1[S:1][CH2:2][CH2:3][CH2:4]2Participants
4
Conditions
- Temperature
- 100 °C
Procedure
1 g (6.015 mmol) of 8-thiochromanol is dissolved in 2.26 g (12.03 mmol) of 1,2-dibromoethane. 5.6 cm3 of a 1.6N NaOH solution are added dropwise. The mixture is heated to 100° C.; after 2 hours, the solution reaches pH 7. The mixture is allowed to cool. 100 cm3 of a 2N NaOH solution are added. The mixture is extracted with CH2Cl2 and then dried over MgSO4. Purification over a silica column (eluant: petroleum ether/CH2Cl2 2: 1) yields the desired compound.