Ultraviolet Photodissociation Dynamics of the Cyclohexyl Radical: The H-Atom Product Channel.

The ultraviolet (UV) photodissociation dynamics of the jet-cooled cyclohexyl (-CH) radical is studied using the high- Rydberg atom time-of-flight (HRTOF) technique. The cyclohexyl radical is produced by the 193 nm photodissociation of chlorocyclohexane and bromocyclohexane and is examined in the photolysis wavelength region of 232-262 nm. The H-atom photofragment yield (PFY) spectrum contains a broad peak centered at 250 nm, which is in good agreement with the UV absorption spectrum of the cyclohexyl radical and assigned to the 3p Rydberg states.

Computational insight into the Rh-mediated activation of white phosphorus.

Density functional calculations on the reaction of white phosphorus with the ligand bis(diphenylphosphino)methyl (dppm) at a rhodium center are presented. The cationic transition metal fragment can react as a nucleophilic as well as an electrophilic species, driven by a simple twisting of the four-membered rings. As a consequence of the conformational controlled philicity, the insertion reaction into white phosphorus occurs with a small energy barrier.