Mesoionic Carbene-Iridium Complex Catalyzed Ortho-Selective Hydrogen Isotope Exchange of Anilines with High Functional Group Tolerance.

Mesoionic carbene-iridium complex 1a has been investigated in the hydrogen isotope exchange (HIE) reaction of anilines. By employing 1 mol % of 1a as catalyst, anilines were selectively deuterated at the ortho-position with high deuteration levels. High ortho-selectivity was observed for anilines with various competing directing groups, which is in contrast with catalytic results of Kerr's catalysts.