Addition to a Double Bond Alkylidene, Imido

Addition of Br0nsted acids to double bonds involving a metal center is well known in molecular chemistry [15]. Therefore, it was expected to take place when complexes bearing an alkylidene or an imido ligand were allowed to react with acidic 

There are no reports of such a reaction with alkylidene complexes of rhenium such as [Re(=CCMe3)(=CHCMe3)(CH2CMe3)2] [21-23], tungsten (]W(=NAr) (=CHCMe3)(CH2CMe3)2]) [24] and other complexes of molybdenum 

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