Parallel mechanistic studies on the counterion effect of manganese salen and porphyrin complexes on olefin epoxidation by iodosylarenes

Oxidation of methionines by oxochromium(V) cations: A kinetic and spectral study

“…The EPR spectra of the oxochromium(V) complexes show a quintet splitting due to 2 equiv nitrogens centered at AEgae 1.978 accompanied by a four-component hyperfine splitting arising from the 53 Cr isotope [26]. The spectroscopic data obtained are close to those of reported by Kochi et al and to isoelectronic [(salen)Cr v "N] + complexes [27,65].…”

“…The metal-complexes derived for the salen ligand are used for the biomimetic oxidation of various organic substrates [24][25][26]. The [(salen)Cr V @O] + ion generated from Cr(III)-salen, has been characterized definitely by spectroscopic techniques and by single crystal X-ray structure determination (see Fig.…”

Synthesis, Characterization, and Reactivities of Manganese(V)−Oxo Porphyrin Complexes

“…This result indicates that the olefin epoxidation is stereospecific, as reported in the epoxidation of cis-stilbene by Mn(TDCPP)Cl and PhIO. 28 Also, as observed in the iron porphyrin-catalyzed epoxidation of trans-stilbene by PhIO, 29 only a small amount of transstilbene oxide was produced in the epoxidation of trans-stilbene (entry 4). In the hydroxylation of alkanes by 1a and PhIO, equimolar amounts of alcohol and ketone products were produced (entries 5 and 6).…”

Synthesis and spectroscopic properties of a nickel(II) complex with a chiral N,N,N′-tri(2-pyridylmethyl)-S-2-(aminomethyl)piperidine=S-P3pipda

“…A number of metal complexes derived from symmetric and chiral diamines have been reported [1e,1f, [4][5][6]. To the best our knowledge, however, only a few complexes with unsymmetrical ligands have been reported [7].…”

“…The nickel(II) complex, 1, exhibits an absorption maxima at 18300 cm À1 (546 nm, e = 15 M À1 cm À1 ) and at 11500 cm À1 (870 nm, e = 17 M À1 cm À1 ), which are characteristic of a high-spin nickel(II) complex. For example, [Ni(NH 3 ) 6 ] 2+ [12] and [Ni II (bipy) 3 ] 2+ [13] which are high-spin hexa-coordinated complexes, exhibit absorption bands at 10750 cm À1 (930 nm), 13150 cm À1 (760 nm) and 17500 cm À1 (571 nm) for [Ni(NH 3 ) 6 ] 2+ and at 28200 cm À1 (355 nm), 12700 cm À1 (787 nm), 11500 cm À1 (870 nm), and 19200 cm À1 (521 nm) for [Ni II (bipy) 3 ] 2+ . The absorption spectrum of 1 is similar to those for [Ni(NH 3 ) 6 ] 2+ and [Ni II (bipy) 3 ] 2+ .…”