Selective Synthesis of 3-(1 H -Tetrazol-5-yl)-indoles from 2 H -Azirines and Arynes.

A new selective synthetic approach to indole derivatives bearing a tetrazole moiety has been developed. Arynes, generated in situ from o -(trimethylsilyl)aryl triflates and KF, reacted smoothly with 2-(2-benzyl-2 H -tetrazol-5-yl)-2 H -azirines to give 3-(2-benzyl-2 H -tetrazol-5-yl)-indole derivatives with high selectivity. Deprotection of the tetrazole moiety gave 3-(1 H -tetrazol-5-yl)-indole derivatives.