2-Pentylthiophene → 2-bromo-5-pentylThiophene
Reaction equation
[CH2:1]([C:6]1[S:7][CH:8]=[CH:9][CH:10]=1)[CH2:2][CH2:3][CH2:4][CH3:5].[Br:11]N1C(=O)CCC1=O.C(O)(=O)C.C(Cl)(Cl)Cl>O>[Br:11][C:8]1[S:7][C:6]([CH2:1][CH2:2][CH2:3][CH2:4][CH3:5])=[CH:10][CH:9]=1Participants
5
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Procedure
A solution of 2-pentylthiophene, (25.2 g) N-bromosuccinimide (25.5 g) and a 1:1 chloroform acetic acid mixture (100 cm3) was heated under reflux for 1 h. Water (10 cm3) was added and the resultant solution stirred for 10 min under an atmosphere of nitrogen. The organic layer was separated off and the aqueous layer extracted with diethyl ether (2×50 cm3). The combined organic layers were washed with brine (2×100 cm3), dried (MgSO4), filtered and then evaporated down. The residue was purified by distillation (Bp 132-134° C. at 15-20 mm Hg.) to yield 32.6 g of 2-bromo-5-pentylthiophene.