A Closer Look at the Bromine–Lithium Exchange with <i>tert</i>-Butyllithium in an Aryl Sulfonamide Synthesis
作者:Christopher Waldmann、Otmar Schober、Günter Haufe、Klaus Kopka
DOI:10.1021/ol4010454
日期:2013.6.21
A practical protocol for the one-pot synthesis of various aryl sulfonamides, notably of pyridine-core-substituted 7-azaindolyl sulfonamides, Is described. A key step is the well-known bromine-lithium exchange reaction of an aryl bromide with tert-butyllithium (t-BuLi). Differing from the common practice to use 2 or more equiv of organolithium, the exact amount of t-BuLi needed for a sufficient exchange reaction Is determined for each aryl bromide in a GC-MS-assisted experiment.