Efficient Regioselective Preparationof Monobromo and Bromoiodo Hydroxy Pyridines from Dibromoderivativesvia Bromine-Lithium Exchange
作者:Mª Ascensión Sanz-Tejedor、Ángela Meana、Justo F. Rodríguez、José L. García-Ruano
DOI:10.1055/s-2003-41013
日期:——
Annular dibromination of hydroxypyridines with NBS in acetonitrilefollowed by bromine-lithium exchange with RLi and subsequent trappingwith H2O or I2 afforded monobromo and bromoiododerivatives in a completely regioselective way. Iodination of bromohydroxypyridines with NIS is totally regioselective.
氢氧嘧啶的环状二溴化反应采用NBS在乙腈中进行,随后与RLi进行溴锂交换,最后用H2O或I2捕获,完全区域选择性地得到了单溴和溴碘衍生物。用NIS对溴氢氧嘧啶进行碘化反应也是完全区域选择性的。