Elimination of benzotriazolyl group in N-(α-benzotriazol-1-ylalkyl)amides and N-(α-benzotriazol-1-ylalkyl)sulfonamides: their self-coupling and cross-coupling reactions with carbonyl compounds

The elimination of benzotriazolyl group from N-(α-benzotriazol-1-ylalkyl)amides and N-(α-benzotriazol-1-ylalkyl)sulfonamides are readily realized with samarium diiodide as a reducing agent. The resulting intermediates undergo a dimerization or cross-coupling reaction with carbonyl compounds, thus affording the corresponding dimers or α-hydroxyalkylated sulfonamides in moderate yields.