Improved light absorbance does not lead to better DSC performance: studies on a ruthenium porphyrin–terpyridine conjugate

Abstract

The preparation and characterization of 7-(4- (

'Active Surfaces' as Possible Functional Systems in Detection and Chemical (Bio) Reactivity

“…Attachment to a TiO 2 surface was easily achieved through the use of phosphonate anchoring-domains, but although the conjugate showed the enhanced light-absorption, the desired electron-injection which was the goal of the assembly, proved inefficient and, in collaboration with the group of Oliver Wenger (University of Basel), we have shown that triplet-triplet energy transfer processes are likely responsible for this poor performance. [7] As shown in the preceding discussion, we have demonstrated the potential of the 'surface-as-ligands' approach for the incorporation of bio-motifs. We are currently extending the approach to functionalization by nano-compartments such as polymersome vesicles.…”

“…1). [7] In this case, significant synthetic effort was required to prepare the conjugate. Attachment to a TiO 2 surface was easily achieved through the use of phosphonate anchoring-domains, but although the conjugate showed the enhanced light-absorption, the desired electron-injection which was the goal of the assembly, proved inefficient and, in collaboration with the group of Oliver Wenger (University of Basel), we have shown that triplet-triplet energy transfer processes are likely responsible for this poor performance.…”

Homoleptic complexes of a porphyrinatozinc(ii)-2,2′:6′,2′′-terpyridine ligand

“…Conjugates incorporating 2,2':6',2"-terpyridine (tpy) are attractive targets for the study of electron and energy-transfer processes and photosynthetic models. 1,2,3,4,5,6,7,8 Functionalization of porphyrin cores with 2,2'-bipyridine 9,10,11,12,13,14,15 or 1,10-phenanthroline 16,17 gives access to systems which can assemble heteroleptic tris(chelate) metal complexes, and a number of multinuclear arrays have been described incorporating pyridine-decorated porphyrins. 18,19,20,21,22 An alternative approach to assembly of metalloporphyrin-centred conjugates makes use of the axial coordination site of the metalloporphyrin, for example by the binding of metal complexes of 4'-(4-pyridyl)-2,2':6',2"-terpyridine.…”

“…However, by utilizing the selective monobromination of 5,10,15,20-tetraphenyl-21H,23H-porphyrin (H 2 TPP) in one pyrrole ring reported by Zhang and coworkers, monofunctionalization of [ZnTPP] with a 4(4'-phenyl-2,2':6',2"-terpyridyl) substituent is readily achieved. 8 Competition between the porphyrin and tpy units for metal ion coordination means that the porphyrin domain should be metallated before the porphyrin core is functionalized with the tpy domain. To date, we have only explored the formation of a single heteroleptic ruthenium(II) complex containing metalloligand 1 (Scheme 1) and we were therefore motivated to explore further the coordination chemistry of this new ligand, and to investigate how the inclusion of the peripheral metalloporphyrin units affect the electrochemical and spectroscopic properties of the complexes.…”

“…23 We recently reported a new strategy for the functionalization of porphyrins in which a tpy domain is attached to a pyrrole ring of the porphyrin core. 8 For synthetic reasons, functionalities are commonly introduced in the mesopositions of the porphyrin ring (5,10,15,20-substitution). However, by utilizing the selective monobromination of 5,10,15,20-tetraphenyl-21H,23H-porphyrin (H 2 TPP) in one pyrrole ring reported by Zhang and coworkers, monofunctionalization of [ZnTPP] with a 4(4'-phenyl-2,2':6',2"-terpyridyl) substituent is readily achieved.…”