Visible light induced formation of a tungsten hydride complex†
Abstract
When irradiated with blue light in the presence of a Lewis base (L), [CpW(CO)3]2 undergoes metal–metal bond cleavage followed by a disproportionation reaction to form [CpW(CO)3L]+ and [CpW(CO)3]−. Here, we show that in the presence of pyridinium tetrafluoroborate, [CpW(CO)3]− reacts further to form a metal hydride complex CpW(CO)3H. The rection was monitored through in situ photo 1H NMR spectroscopy experiments and the mechanism of light-driven hydride formation was investigated by determining quantum yields of formation. Quantum yields of formation of CpW(CO)3H correlate with I−1/2 (I = photon flux on our sample tube), indicating that the net disproportionation of [CpW(CO)3]2 to form the hydride precursor [CpW(CO)3]− occurs primarily through a radical chain mechanism.
- This article is part of the themed collection: Spotlight Collection: Photoinduced redox chemistry