Transition metal bridged system

It is interesting to note here the contributions recently made by D. W. Bennett and his student, J. S. Rommel (66) in the new series of organic bridging groups. Diisocyanobenzene (CN-C H -NC) is used to link two transition metals. These systems can possibly be joined together to form an electronically conducting polymer. 

Similar stability and reactivity have also been observed for bridged-Cp systems. The catalyticaHy active (CH2)2Si(C (CH2)4)2ThR2, where R = Cl [89597-06-8] alkyl, CH2CgH [89597-10A] aryls, or H [89597-11-5], Similar to Group 4 transition-metal Zeigler-Natta catalysts, stable cationic Th(IV) species, eg, [Cp 2ThCH2] [108834-69-17, have been isolated with a host of noncoordinatiag/nonreactive anions. MetaHacycle formation has also been... 

AT-Heteroaryl ring systems are well-known as bridging functions between transition metal centers [12, 40, 41]. The pyridyl substituent is one of the representative examples of such systems that has been a widely used ligand in transition metal coordination chemistry [42]. However, the interest in group 13 metal chemistry of these ligands is of recent interest. Stalke et al. [43] have reported the synthesis and structure of the aluminum adduct Me3Al(/r-Py)PPy2 10. 

Wagner and co-workers have reported the synthesis of ferrocene-bridged tris(l-pyrazolylborate) oligomeric systems (80) (Fig. 49).62 Such polymers are of interest, as they offer a multiplicity of options for tailoring the access space to a metal held by the tris(l-pyrazolylborate) ligand, as well as a means to electronically influence the environment of a transition metal.113,114... 

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