反应详情

1-(3-Bromophenyl)-2-thiourea (Oakwood Products, Inc., West Columbia, S.C.; 2.479 g, 10.73 mmol) was suspended in MeCN (200 mL) and cooled in an ice water bath under nitrogen. Then, a solution of bromine (1.1 mL, 21 mmol) in acetic acid (10 mL) was added dropwise over 15 minutes. The reaction was stirred while being cooled in an ice water bath for 30 minutes, then allowed to warm to RT while stirring over the weekend. The resulting precipitate was filtered and the solid was washed with Et2O to afford the mixture (2.5 g, 100% yield) of 7-bromobenzo[d]thiazol-2-amine and 6-bromobenzo[d]thiazol-2-amine in a 1:2 ratio. MS (ESI pos. ion) m/z: 229 (MH+, 79Br), 231 (MH+, 81Br). Calculated exact mass for C7H5BrN2S: 228 (79Br), 230 (81Br).

1. temperaturecooled in an ice water bath under nitrogen
2. temperaturewhile being cooled in an ice water bath for 30 minutes
3. stirringwhile stirring over the weekend
4. filtrationThe resulting precipitate was filtered
5. washthe solid was washed with Et2O