Transition metals silene complexes with

In 1988, Tilley and coworkers first succeeded in the synthesis of a ruthenium-silene complex by the reaction of Cp Ru(PR3)Cl with a Grignard reagent, and the structure was confirmed by X-ray crystallography (Eq. 9) [10]. They later synthesized an iridium complex in a similar manner (Eq. 10) [11]. Berry synthesized a tungsten-silene complex by treatment of a tungsten-chloride complex with Mg (Eq. 11) [12]. Although reactions of transition metal-silene complexes with Mel, HX, and MeOH have been reported, little is known about their reactivities [11,12]. 

To examine the reactivity of a zirconium-silicon bond, Mori et al. synthesized a zirconium-silicon complex from Cp2ZrCl2 and Ph/BuSiLi (1 equiv.) and investigated the reactivity of this complex [ 14]. Furthermore, they found that the reaction of Cp2ZrCl2 with 2 equivalents of Me2PhSiLi gave disilylzirconocene, which was easily converted into a zirconium-silene complex via /J-hydrogen elimination (Scheme 1) [15]. This is the first example of the formation of an early transition metal-silene complex. In this chapter, the reactivity of the zirconium-silene complex is described. 

Major advances in organometallic chemistry during the last years have been achieved in the area of silicon-metal multiple bonding and silicon with low coordination numbers. For late transition metals, new complexes have been synthesized such as silanediyl (A), silene (B), silaimine (C), disilene (D), silatrimethylenemethane (E), silacarbynes (F), cyclic silylenes (G), silacyclopentadiene (H) and metalla-sila-allenes (I) (Figure 3). 

Given the ability of transition-metal complexes to stabilize species via coordination, it is reasonable to expect that given the proper choice of transition metal fragment L M, silene complexes can be isolated and studied. As with analogous alkene coordination... 

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