Synthesis of a copper-supported triplet nitrene complex pertinent to copper-catalyzed amination

Terminal copper-nitrenoid complexes have inspired interest in their fundamental bonding structures as well as their putative intermediacy in catalytic nitrene-transfer reactions. Here, we report that aryl azides react with a copper(I) dinitrogen complex bearing a sterically encumbered dipyrrin ligand to produce terminal copper nitrene complexes with near-linear, short copper–nitrenoid bonds [1.745(2) to 1.759(2) angstroms]. X-ray absorption spectroscopy and quantum chemistry calculations reveal a predominantly triplet nitrene adduct bound to copper(I), as opposed to copper(II) or copper(III) assignments, indicating the absence of a copper–nitrogen multiple-bond character. Employing electron-deficient aryl azides renders the copper nitrene species competent for alkane amination and alkene aziridination, lending further credence to the intermediacy of this species in proposed nitrene-transfer mechanisms.

Source: ScienceNOW - September 11, 2019 Category: Science Authors: Carsch, K. M., DiMucci, I. M., Iovan, D. A., Li, A., Zheng, S.-L., Titus, C. J., Lee, S. J., Irwin, K. D., Nordlund, D., Lancaster, K. M., Betley, T. A. Tags: Chemistry r-articles Source Type: news