Singly Metallated Trisilacyclohexanes

These reactions are understood to operate through nucleophilic substitution of the brominated Si atom, whereby the carbonylate anion attacks the electropositive Si 

If the stabilities of all the compounds shown in Tab. 63 are compared, 375 is found to be the most stable to oxidation. Considerably more reactive are 372, 373 and especially 376, while their Mn(CO)5- and cp(CO)3W-substituted derivatives have an intermediate reactivity. Compounds 371, 372 and 373 are inherently more stable against more polar solvents such as Et20 and THF, and also against irradiation, than R3Si—M(CO)3cp (M = W, Mo, Cr) [164]. NMR and IR investigations indicate that because of metal substitution, a weakening of the Si-H bond of the metal-substituted Si atom will occur. 

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