Bromine → 2-Amino-5-methoxy-7-phenylbenzothiazol
Reaction equation
[CH3:1][O:2][C:3]1[CH:4]=[C:5]([NH:15][C:16]([NH2:18])=[S:17])[CH:6]=[C:7]([C:9]2[CH:14]=[CH:13][CH:12]=[CH:11][CH:10]=2)[CH:8]=1.BrBr>C(Cl)(Cl)Cl>[CH3:1][O:2][C:3]1[CH:8]=[C:7]([C:9]2[CH:14]=[CH:13][CH:12]=[CH:11][CH:10]=2)[C:6]2[S:17][C:16]([NH2:18])=[N:15][C:5]=2[CH:4]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 61 °C
Procedure
(5-Methoxy-biphenyl-3-yl)-thiourea (109 mg, 0.42 mmol) in chloroform (2 ml) are treated with bromine (22 μl) and the mixture heated to 61° C. for 5 hours. After removal of the volatile components in vacuo, the product (93 g, 86%) is isolated by flash chromatography (silica, eluent ethyl acetate/cyclohexane 2:1 to 5:1) as beige solid. The regiochemistry of the cyclization was checked by transfer-NOE measurements. MS: m/e=256 (M+).