Employing time-resolved IR spectroscopy, we have demonstrated that, following photolysis of Cr(CO)4-(bpy) (1) in CH2Cl2, the only detectablephotoproduct on the 50 ns time scale is the solvated CO-loss intermediate fac-Cr(CO)3(bpy)(CH2Cl2) (2); this intermediate is formed following either MLCT (532 nm) or LF (355 nm) excitation. The rate of the back-reaction of 2 with CO has been measured (k2 = 7.1 (±0.5) × 706M-1 s-1); in the presence of PPh3, the intermediate 2 reacts to produce fac-Cr(CO)3-(bpy)(PPh3) (3) exclusively (k2 = 1.0(±0.5)× 1.07 M-1 s-1). From UV/visible flash photolysis data, we conclude that this intermediate 2 is probably produced on a ps / subps time scale.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry