Transition metal complexes hemilabile

Figure 2.3 Two transition metal complexes featuring hemilabile phosphane ligands 119,26],...

Figure 2.4 Two transition metal complexes with hemilabile functionalised NFfC ligands.

In this chapter, we focus on P,N-chelating ligands and some of their transition metal complexes because their intrinsic properties, immense structural diversity, and broad range of applications attract increasing attention [3]. Such heterofunctional ligands associate hard nitrogen donor(s) with soft phosphoms donor(s) and offer considerable chemical and structural diversity. They may also generate hemilabile systems endowed with enhanced reactivity. 

D. A. Weinberger, T. B. Higgins, C. A. Mirkin, L. M. Liable-Sands and A. L. Rheingold, Terthienyl-based redox-switchable hemilabile ligands transition metal polymeric complexes with electrochemically tunable or switchable coordination environments, Angew. Chem. Int. Ed., 38, 2565-2568 (1999). 

It is also important to note that the hybrid calixphyrin-palladium and -rhodium complexes catalyze the Heck reaction (p-bromobenzaldehyde with n-butyl acrylate in A, A -dimethylacetamide at 100 °C) and hydrosilylations (acetophenone with Ph2SiH2 and of phenylacetylene with PhMe2SiH), respectively, with high efficiency. The present results demonstrate the potential utility of the phosphole-containing hybrid calixphyrins as highly promising hemilabile macrocyclic ligands for the construction of efficient transition-metal catalysts [160, 162]. 

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