Synthesis of a new polypyridinic highly conjugated ligand with electron-acceptor properties

Synthesis, Characterization, and DNA Binding Properties of Ruthenium(II) Complexes Containing the Redox Active Ligand Benzo[i]dipyrido[3,2-a:2′,3′-c]phenazine-11,16-quinone

“…More recently, the Liu and Hauser groups have employed aqphen as an acceptor moiety in the construction of Ru II -based chromophore quencher systems that display long-lived charge separated states . In related work, the Loeb group has also described the five step synthesis of an analogue of aqphen, benzo[ i ]dipyrido[3,2- a :2′,3′- c ]phenazine-11,16-quinone (qdppn) and briefly outlined the syntheses and absorption spectra of two [Re(L)CO) 3 (qdppn)] complexes (L = Cl, CF 3 SO 3 ) . In a later study, Rao et al revealed that photoirradiation of the complex [Ru(dtb-bpy) 2 (dppn)] 2+ (dtb-bpy = 4,4-di- tert -butyl-2,2-bipyridine; dppn = benzo[ i ]dipyrido[3,2- a :2′,3′- c ]phenazine) in aerobic conditions produced [Ru(dtb-bpy) 2 (qdppn)] 2+ in essentially quantitative yields .…”

A Fused Donor−Acceptor System Based on an Extended Tetrathiafulvalene and a Ruthenium Complex of Dipyridoquinoxaline

“…First we developed an efficient synthesis of the ligand Nqphen 7 . This key building block was previously prepared in five steps and in an overall 30% yield from 2,3-dichloronaphthoquinone . We performed the synthesis of this ligand in three steps in an overall 79% yield (Scheme ).…”

“…Nqphen ligand 7 was isolated in 93% yield as a pale greenish powder from condensation of compounds 5 and 6 in glacial acetic acid. It should be noted that complexes (Nqphen)Re(CO) 3 Cl and (Nqphen)Re(CO) 3 (OTf) were previously reported in the literature . The ruthenium(II) complex 8 was prepared by reaction of Nqphen 7 with Ru(bpy) 2 Cl 2 in refluxing ethanol.…”

“…18 This key building block was previously prepared in five steps and in an overall 30% yield from 2,3dichloronaphthoquinone. 19 We performed the synthesis of this ligand in three steps in an overall 79% yield (Scheme 2). Compound 5 was prepared in 85% yield according to a two-step procedure from commercially available 2,3-dichloronaphtoquinone.…”

“…It should be noted that complexes (Nqphen)Re(CO) 3 Cl and (Nqphen)Re(CO) 3 (OTf) were previously reported in the literature. 19 The ruthenium(II) complex 8 was prepared by reaction of Nqphen 7 with Ru(bpy) 2 Cl 2 22 in refluxing ethanol. Treatment with an aqueous solution of NH 4 PF 6 was followed by purification by flash chromatography on deactivated alumina using acetonitrile as the eluent.…”