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Inclusion of Copper(I) into a Novel Bipyridine-Containing Tetraphosphadiplatinacyclophane

“…This was accompanied by a change in color from deep red to green. [33] Obviously, the above-mentioned stabilization of the bis(bipyridine)copper(I) complex does not include inertness toward oxygen, which can only be achieved by the introduction of substituents at the 6-position. [34,35] On the other hand, such air-sensitive bis(bipyridine)copper(I) systems have applications in the field of redox catalysis.…”

Enol Cation Radicals in Solution, 9. Synthesis and One‐Electron Oxidation Chemistry of Novel, Stable Conjugated Dienols and Yne‐Enols

“…Not unexpectedly, the oxidation potentials of E l -E5 do not differ substantially from those of enols with R = alkyl, e.g. R = Me (Epa = 0.68 V), since even with R = Ph (I$<% = 0.61 V) no major potential shift was observed [12]. These results indicate that the HOMO energy of systems El-E5 is mainly determined by the overlap of both mesityl groups with the enol functionality, although the aryl groups are severely twisted out of the enol Our semiempirical calculations (AM 1) confirm the assumption derived from the experimental data that the two double bonds of the dienols El-E3 are indeed in full conjugation, the s-trans rotamer constituting the global minimum.…”

“…Certainly, enol cation radicals should be formed with our oxidants on the basis of redox potential considerations. Earlier studies [9][10][11][12] revealed that the primary reaction of enol cation radicals involves deprotonation of these acidic intermediates to the corresponding a-carbonyl radicals. Since the reactions were performed under oxidative conditions, the resulting a-carbonyl radicals R should be oxidized even more rapidly than the enols as judged from the oxidation potentials of similar systems['*].…”

Grids with Unusual, High Nuclearity – A Structural Approach

“…Heteroleptic [2 × 3] grids containing two types of ligands were reported,37a,37b and this sparks interest for heteroleptic grids that would contain three or more types of ligand. Another interesting field would be that of grids generated by dissymmetric ligands.…”

“…Di‐ ( 5 ) and tritopic ( 6 ) ligands incorporating two and three phenanthroline‐derived bidentate sites connected through 1,4‐diethynyl‐benzene units, respectively, were synthesized in the framework of the interesting HETPHEN concept,37b where bulky aryl substituents (like R 1 and R 3 in 5a and 6a ; see Figure 2c) produce steric and electronic effects inducing the shift of the coordination equilibrium toward the formation of heteroleptic complexes. [2 × 3]heteroleptic hexanuclear grids37c [Cu 6 ( 5a ) 3 ( 6b ) 2 ] 6+ (Figure 16) and [Cu 6 ( 5b ) 3 ( 6a ) 2 ] 6+ slowly form as the product of the reaction of 5a and 6b and 5b and 6a , respectively, with [Cu(MeCN) 4 ]PF 6 in dichloromethane ( 5 / 6 /Cu I = 3:2:6).…”