Activation of the sulfhydryl group by Mo centers: kinetics of reaction of benzyl radical with a binuclear Mo(micro-SH)Mo complex and with arene and alkane thiols.

This paper provides evidence from kinetic experiments and electronic structure calculations of a significantly reduced S-H bond strength in the Mo(micro-SH)Mo function in the homogeneous catalyst model, CpMo(micro-S)(2)(micro-SH)(2)MoCp (1, Cp = eta(5)-cyclopentadienyl). The reactivity of 1 was explored by determination of a rate expression for hydrogen atom abstraction by benzyl radical from 1 (log(k(abs)/M(-)(1) s(-)(1)) = (9.07 +/- 0.

Absolute rate constants for reactions of tributylstannyl radicals with bromoalkanes, episulfides, and alpha-halomethyl-episulfides, -cyclopropanes, and -oxiranes: new rate expressions for sulfur and bromine atom abstraction.

Arrhenius rate expressions were determined for the abstraction of bromine atom from 2-phenethyl bromide by tri-n-butylstannyl radical (Bu(3)Sn(*)) in benzene using transient absorption spectroscopy, (log(k(abs,Br)/M(-1) s(-1)) = (9.21 +/- 0.20) - (2.