A Search for the Influence of the Electronic Characteristics of the Camphor Derived Ligands and Complexes on their Redox Properties

Abstract

The electrochemical data obtained by cyclic voltammetry on several camphor-type (A,

Intramolecular Charge Transfer in Ruthenium Complexes [Ru(acac)2(ciq)] with Ambidentate Camphoriminoquinone (ciq) Ligands

“…A nonaromatic system with a structurally well‐defined rigid bicyclic framework and an α‐dione function is the so‐called camphorquinone (cq, see Figure 1) which can be converted into a redox‐active (Figure 2) monoimine derivative [9,10] . Some coordination compounds of N‐organo‐camphoriminoquinone (ciq) ligands have been investigated structurally [10,11] and with respect to potentially catalytic properties [10–12] …”

“…Chelate ligands derived from camphorquinone are rare, the diimine variant has been employed in iron and nickel complexes, [17,18] with variably discussed oxidation state assignments [17] . Monoimines as those in Figures 1 and 2 were used in connection with catalysis or biological activity [10–12] …”

“…[17] Monoimines as those in Figures 1 and 2 were used in connection with catalysis or biological activity. [10][11][12]…”

“…[9,10] Some coordination compounds of N-organocamphoriminoquinone (ciq) ligands have been investigated structurally [10,11] and with respect to potentially catalytic properties. [10][11][12] In the present report we describe the results from reactions of the π accepting N-phenylcamphoriminoquinone (pciq, Figure 1) and of the o-thiomethyl-modified analogue N-(2thiomethylphenyl)-camphoriminoquinone (tciq) with strongly π donating {Ru(acac) 2 }, acac À = 2,4-pentanedionate. [13] Thiomethyl substituents have been used in noninnocent hemilabile benzenoid ligands [14][15][16] whose structure (coordination) and spin-spin coupling pattern depend on the redox state of the metal complexes.…”