Comparison of electron spin relaxation times measured by Carr–Purcell–Meiboom–Gill and two-pulse spin-echo sequences
作者:James R Harbridge、Sandra S Eaton、Gareth R Eaton
DOI:10.1016/s1090-7807(03)00182-4
日期:2003.9
Electron spin relaxationtimes obtained by two-pulse spin-echo and Carr-Purcell-Meiboom-Gill (CPMG) experiments were compared for samples with: (i) low concentrations of nuclear spins, (ii) higher concentrations of nuclear spins and low concentrations of unpaired electrons, (iii) higher concentrations of nuclear spins and of electron spins, and (iv) dynamic averaging of inequivalent hyperfine couplings
substituents and their contribution to the O−H bond dissociation enthalpy (BDE) in phenolic compounds. A series of ortho- and para-(S,Se,Te)R-substituted phenols were prepared and investigated by EPR, IR, and computational methods. Substituents lowered the O−H BDE by >3 kcal/mol in the para position, while the ortho-effect was modest due to hydrogenbonding (∼3 kcal/mol) to the O−H group.
关于有机硫属元素取代基的ED / EW特性及其对酚类化合物中O-H键离解焓(BDE)的贡献知之甚少。制备了一系列邻-和对-(S,Se,Te)R取代的酚,并通过EPR,IR和计算方法进行了研究。取代基降低了O - H BDE由> 3千卡/摩尔在对位位置,而邻-效应是氢键适度由于(〜3千卡/摩尔)向O-H基团。
Reaction of superoxo Co(III) complex with stable phenoxy radicals
作者:A. Nishinaga、H. Tomita、T. Matsuura
DOI:10.1016/s0040-4039(00)78701-6
日期:1980.1
A typical superoxocomplex [Co(CN)5O2][Ph3PNPPh3]3 combines with stable phenoxy radicals in CH2Cl2 leading to selective formation of peroxy--quinols except for 2,4,6-tri--butylphenoxy radical, representing radical reactivity of the complex.
Convenient unimolecular sources of aryloxyl radicals I -- aryloxyoxalyl chlorides
作者:David A. Modarelli、Frank C. Rossitto、Paul M. Lahti
DOI:10.1016/s0040-4039(01)80721-8
日期:1989.1
UV photolysis of readily synthesized aryloxyoxalyl chloride half-esters provides a new unimolecular source of aryloxylradicals, as shown by ESR and UV-vis spectroscopy.
Convenient unimolecular sources of aryloxyl radicals. III - photolysis of bis(aryloxy)phosphine azides
作者:Rajdeep Kalgutkar、Alexey S. Ionkin、Louis D. Quin、Paul M. Lahti
DOI:10.1016/s0040-4039(00)76694-9
日期:1994.6
Photolysis of sterically hindered bis(aryloxy)phosphine azides in solution, frozen matrix, or neat solid states leads to facile unimolecular production of aryloxylradicals.