Identification by EPR of Cu(C5H5N)52+ species in the homogeneous oxidative coupling reaction of phenylacetylene catalyzed by Cu(C5H5N)4 (NO3)2

Acetylenic Coupling: A Powerful Tool in Molecular Construction

“…Acetylene activation by p-complex formation postulated by Bohlmann et al [146] Bohlmann et al also called into question the idea of free radical intermediates, noting that mixtures of electronically different alkynes give predominantly the homocoupled products, whereas no such selectivity would be expected of free radicals. [149] Studies by Fedenok et al largely confirmed these results. Such an intermediate also rationalized the firstorder dependence of the rate on the substrate concentration observed during intramolecular coupling to generate cyclic diynes.…”

EPR and Spectral Studies of a Molecular and Crystal Structure of Cu (3,5-dimethylpyridine)3(NO3)2

“…Liquid solutions spectra at 292 K and frozen solution (77 K) spectra are shown in Fig. 4 and EPR parameters are summarized in Table. The spectra and parameters are typical for Cu(H) coordinated by aromatic amines [10][11][12] with a relatively well resolved superhyperfine pattern from 14 N atoms on the perpendicular peak. Number of the superhyperfine structure lines is 7 or 8.…”

Aerobic Copper-Catalyzed Organic Reactions

“…1070 This species is postulated to then dimerize and subsequently expel dioxygen after two-electron reduction from copper. In this mechanism, the role of oxygen is formation of the nitrosobenzyl radical as opposed to oxidation of a reduced copper species.…”