in toluene Kinetics; byproducts: tris(p-tert-butylphenyl)methane; mixing of a toluene soln. of radical with a toluene/metal hydride under Ar or N2; kinetic measurements in a stopped-flow apparatus (-40 to 50°C), monitoring of react. by UV (523 nm), thermodynamic data and rate const. for react. at 25°C; products not isolated, detd. by UV, IR;