Disilenide

The disilenides 5 NaX may be transformed into 12ci, Br. i by reaction with any of the other compounds present in solution, namely the disilanides 2 NaX or the disilenes 2 as precursors of 5 NaX, and the disilyne 5 may be a possible product of 5 NaX (cf Scheme 7.2). In fact, insertions of 2 into the NaSi bond of 5 NaX or of 5 into the NaSi bond of 2 NaX or 5 NaX are quite probable. The formed tetrasilenides Na-R XSi-SiXR -R. Si SiXR or Na-R 5 z-5 /R -R XSi-SiX2R may then transform via R XSi=SiR -R Si=SiXR or directly into 12a, Br, i- So far, we have been unable to trap the disilyne 5, a result that neither proves or disproves the intermediacy of such a disilyne. ... 

The novel 7 -disilenide zirconium complex 44 is highly reactive and undergoes ready rearrangement via addition of a methyl C-H bond to the Si=Si bond to give the silyl zirconium complex 45, as a mixture of diastereoisomers, shown in Equation (5) <2005JA10174>. 

Metal-substituted silicon analogs of alkenes, the disilenides, possess a prefabricated silicon—silicon double bond (1). Such compounds are important from the perspective of being sp -type silyl anions which are a powerful synthetic tool in organosi-licon chemistry (2). In particular, the disilenyl anions have been a focus of intensive investigation since these can act as excellent disilene (Si=Si) transfer agents (1). 

Scheme 6.2.2.2 Reaction of Disilenide with Tris(3,5-di-tbutylphenyl)acetaldehyde (Ar = 3,5-di-tbutylphenyl).

LITHIUM TRIS(2,4,6-TRIISOPROPYLPHENYL) DISILENIDE A VERSATILE REAGENT FOR THE TRANSFER OF THE DISILENYL GROUP... 

Equation 9. Disilastannirane formation by reaction of a lithium disilenide with Me2SnCl2. 

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