Elusive Terminal Copper Arylnitrene Intermediates.
Abolghasem Gus Bakhoda1, Quan Jiang2, Jeffery A Bertke1
1Department of Chemistry, Georgetown University, Box 571227, Washington, DC 20057-, 1227, USA.
Angewandte Chemie (International Ed. in English)
|May 5, 2017
Summary
This study reveals novel copper-catalyzed reactions with aryl azides, forming triazenido complexes and terminal nitrenes. These nitrenes act as masked intermediates for group transfer reactions.
Area of Science:
- Organometallic Chemistry
- Catalysis
- Synthetic Chemistry
Background:
- Copper(I) complexes with bulky ligands are valuable catalysts.
- Aryl azides are versatile precursors in organic synthesis.
Purpose of the Study:
- To explore new reactivity modes between aryl azides and a bulky copper(I) β-diketiminate complex.
- To characterize the resulting products and understand their reaction pathways.
Main Methods:
- Reaction of [iPr2NN]Cu(NCMe) with various aryl azides.
- Spectroscopic characterization of reaction products.
- Reactivity studies including nitrene group transfer.
Main Results:
- Three new reactivity modes were observed: triazenido complex formation, terminal nitrene generation, and subsequent dimerization or nitrile insertion.
- The dicopper(II) diketimide and diazametallocyclobutene complexes were identified as "masked" terminal nitrene precursors.
- Successful nitrene group transfer to phosphines, isonitriles, and benzylic C-H bonds was demonstrated.
Conclusions:
- The bulky copper(I) β-diketiminate facilitates diverse transformations of aryl azides.
- The "masked" nitrene intermediates offer a controlled method for nitrene group transfer reactions.
- This work expands the synthetic utility of copper-nitrene chemistry.
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