Carbene-tellurium adducts as colorimetric probes for the stereo-electronic profiles of carbenes in solution, and as carbene-transfer agents.

To evaluate the electronic and steric properties of carbenes, several techniques have been developed. Herein, we report the use of UV-visible spectroscopy as a stereo-electronic dual probe of carbenes in solution, complementing current methodologies that mostly rely on NMR spectroscopy of rather exotic nuclei and X-ray crystal structures in the solid state. Additionally, we show that carbene-tellurium adducts can act as carbene transfer agents towards other chalcogens and even metals.