Radical-based reducing agents

Substitution at the SiH moiety has been carried out with alkylthio groups, such as MeS and i-PrS. Tn s(alkylthio)silanes, (RSlsSiH, are radical-based reducing agents which can effect the reduction of bromides, iodides, xanthates, phenylselenides, and isocyanides in toluene, using AIBN as the initiator at 85... 

Poly(hydrosilane)s have been used as radical-based reducing agents for organic halides (RX, where X = Cl, Br, 1), rivaling the effectiveness of the (TMSlsSiH. A rate constant (fcn referring to each SiH moiety) in the range of (5-60) xlO M s is estimated for the reaction of primary alkyl radicals with 123. ... 

Scheme 4.8 Silylated cyclohexadienes as radical-based reducing agents...

C. Chatgilialoglu, Organosilanes as radical-based reducing agents in synthesis, Acc. Chem. Res. 25 188 (1992). 

Trimethylsilyl-substituted silanethiols, such as (2) and (3), were shown to be extremely efficient radical-based reducing agents [265]. These agents... 

M. Ballestri, C. Chatgilialoglu, and G. Seconi, (MOjSiljSiSH A new radical-based reducing agent, 5. Organomet. Chem, 408 C1-C4 (1991). 

Tris(trimethylsilyl)silane Historical Perspective and What Can Be Done 20 Years After its Discovery as a Radical-based Reducing Agent... 

Poly(phenylsilane)s have been used as radical-based reducing agents for organic halides [70]. The reduction of a bromide is given as an example in Eq. (32). 1,1,2,2-Tetraphenyldisilane has also been introduced as a diversified radical reagent for the reduction of alkyl bromides and phenyl chalcogenides [71]. An example with 3-cholestanyl phenyl selenide is given in Eq. (33). 

The facts that thiols are good H-atom donors toward alkyl radicals and that silyl radicals are among the most reactive known species for abstraction and addition reactions suggest that any class of compounds which allows the transformation of a thiyl to a silyl radical via a fast intramolecular rearrangement will potentially be a good radical-based reducing agent. The silanethiols 11 and 12 are found to have this property [84, 85]. The reductions of bromides, iodides and isocyanides by thiol 12 are demonstrated to follow the expected mechanism [85]. 

Dihydro-9-sila-10-heteroanthracenes are a class of radical-based reducing agents. They effect reductive debromination and deoxygenation of alcohols via 0-thiocarbonyl derivatives. ... 

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