Macrocyclization transition metal mediated

A review13 with 53 references of the transition-metal mediated supramolecular self-assembly is presented. Focus is on the self-assembly of macrocycles, catenanes, and cages from (en)Pd(N03)2 and pyridine-based bridging ligands. 

An alternative method for producing P4 macrocycles is via transition metal-mediated addition of P—H functions across olefinic double bonds as in Scheme 6. Treatment of the resulting complex with H202 and CN gives the corresponding phosphine oxide macrocycle.2,24 Various reactions at the coordinated PNEt2 function in the coordinated macrocycle have also been investigated.25... 

The prototypical photochemical system for CO2 reduction contains a photosensitizer (or photocatalyst) to capture the photon energy, an electron relay catalyst (that might be the same species as the photosensitizer) to couple the photon energy to the chemical reduction, an oxidizable species to complete the redox cycle and CO2 as the substrate. Figure 1 shows a cartoon of the photochemical CO2 reduction system. An effective photocatalyst must absorb a significant part of the solar spectrum, have a long-lived excited state and promote the activation of small molecules. Both organic dyes and transition metal complexes have been used as photocatalysts for CO2 reduction. In this chapter, CO2 reduction systems mediated by cobalt and nickel macrocycles and rhenium complexes will be discussed. 

Schmiegel, J, and Griitzmacher H.-F. (1990). A macrocyclic 2,19-dioxo[3.3](3,3 )azoben-zolophane by transition metal carbonyl complex-mediated CO insertion and cyclization. Chem Ber. 123,1749-1752. 

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