Oligosilanes reductive

Reduction of the Si-Si bond of oligosilanes with organo- or silyllithium reagents (Scheme 2.44, A,... 

Stable ladder oligosilanes are also of interest. The potassium metal reduction of the neutral ladder oligosilanes containing 6-12 silicon atoms fully substituted by isopropyl groups leads to the formation of corresponding anion-radicals that are highly stable at room temperatnre (Kyushin et al. 2000). These silanes can be nsed as electric switchers. 

TABLE 4. Metalated oligosilanes prepared by reductive cleavage of a Si-Si bond by means of alkali metals... 

The first disilene with an endocyclic double bond, the tetrasilacyclobutene 141b, was prepared by Kira and coworkers through reductive coupling and debromination of the oligosilanes 147 and 148 however, the yield of the pure, isolated product was merely 1.5% (equation 33)136. 

A second cyclotrisilene, compound 153, was isolated after reductive dehalogenation of a mixture of the oligosilanes 148 and 152 (equation 38)141. 

The reaction of PhSiH3 with the Ni-Me precursors has been shown to result in the formation of oligosilanes (PhSiH) . The initial step of this reaction is believed to go through a concerted a-bond metathesis (Kh/Kq 10), but multiple intermediates are formed in the later stages of the catalysis, some of which result from the reductive elimination (see Reductive Eliminatioii) of the indenyl ligand (Scheme 8). ... 

Besides the reversible waves of the ferrocene donor near 0 V two irreversible waves are shown by the cyclic voltammograms of 1 and 2. They are easily assigned to reduction of the -CH=C(CN)2 acceptor and to oxidation of the oligosilane spacer by comparison with proper reference substances (see Table 2). 

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