Imidazoline-1-oxyl

The interaction of imidazoline nitroxide (759) with isocyanates leads to oxadi-azolidines (760), which can be easily transformed into 4/Camino-3-imidazoline-1-oxyls (761) on treatment with nucleophilic reagents (Nu = Nal, NaN3, NH4OH, AcONa, NaH) (Scheme 2.313) (835). 

Tetramethyl-2-(6-bromo-2-pyridyl)-4 -imidazoline-1-oxyl cadmium(II) follows Ci2Hi5BrN30Zn... 

Tetramethyl-2-(2-pyridyl)-d -imidazoline-1 -oxyl mercury(II) follows Ci2Hi6CdN30... 

Tetramethyl-2-(3-bromophenyl)-zl -imidazoline-1-oxyl mercury(II) follows Ci3Hi,HgN20... 

Still greater stability in strong acids is displayed by such nitroxides as quaternary immonium salts 24. These salts are formed in quatemization of imidazoline-1-oxyls 13 with dimethyl sulfate (Volodarsky et al, 1979). They are stable, yellow, high-melting crystalline products, with an ESR spectrum in the form of a triplet with 14.0 Oe. Salts 24 are soluble in water, stable in aqueous solutions, and, when treated with 57% perchloric... 

Imidazoline-oxyl complexes have been studied, and the ligand in [ZnLj (HL = 58) has been shown to be coordinated via the oxygen atom of the carbonyl group and a deprotonated hydroxy group.435... 

The complexes ML2(Si03) (M = Zn, Cd or Hg L = ethylenethiourea) contain bidentate chelating 8203 . Paramagnetic imidazoline oxyl complexes [ML2] (M = Zn or Cd HL = 129) show an unusual electron exchange phenomenon between the two ligands. ... 

HPA = (4-pyridylthio)aceticacid 2-fur = 2-furoate a-fur = a-furoate = ([Pg.116]

Thermolysis of a stable radical 4-[(hydroxyimino)nitromethyl]-2,2,5,5-tetra-methyl-3-imidazolin-l-oxyl 13 gives the corresponding spin-labeled nitrile oxide. It was also identified in isoxazolines formed in cycloadditions with olefins (88). 

A detailed analysis of photoisomerization of the nitrone group in the nitroxyl radical 4-phenyl-2,2,5,5-tetramethyl-3-imidazoline-3-oxide-l-oxyl, based on double electron-nuclear resonance methods, has shown that in the absence of oxygen the photochemical reaction occurs without affecting the radical center. The... 

A recent report shows that 1,2,3,4-benzotetrazine 1,3-dioxide nitroderivatives 73 (R=N O2) are thiol dependent N O-donors and potent activators of the sGC [73]. Activation of the sGC was inhibited in the presence either of ODQ or of the N O scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethy]imidazoline-l-oxyl-3-oxide (carboxy-PTIO). All products inhibited A DP-induced aggregation of human platelets, with the potency sequence 7-nitro >5,7-dinitro >5-nitro. 

Earlier, an ESR investigation of complexes formed between Zn, Cd and Hg and several paramagnetic imidazolin-l-oxyl free radicals had been reported.437 For a given ligand, the changes in the 14N hyperfine splittings can be correlated with the formation constants, and the following order of stability is observed Hg>Cd>Zn. 

In the complex ZnL2-2H20 (HL = 2,2,5,5-tetramethyl-3-imidazoline-3-oxo-l-oxyl-4-... 

Recently, [Co(hfac)2(NITPhOMe)] (NITPhOMe = 4 -methoxy-phenyl-4,4,5,5-tetramethyl-imidazoline-l-oxyl-3-oxide) (1-D helix Scheme 5d) was prepared, whose chains are magnetically isolated from each other. This is considered to be molecular magnetic nanowire. 

Xep2 added to a soln. of l-nitroso-2,2,5,5-tetramethyl-4-phenyl-3-imidazoline 3-oxide in methylene chloride in a Teflon-type vessel, and stirred at 20-25° for 20 h 3-nitroso-2,2,4,4-tetramethyl-5-phenyl-5-fluoroimidazolidine 1-oxyl. Y 70%. F.e. and 1,1-difluoro-N-oxide radicals s. I.A. Grigorev et al., Izv. Akad. Nauk SSSR Ser. Khim. 1989, 933-7. 

C,<,H CuN40, Bis(2,2,5,5-tetramethyl-3-imidazoline-l-oxyl-4-carboxy) copper(II) Nr. 120 Chemical synthesis from stable components/ Acetone glassy solution EPR/ sol 2.041 II 2.089 1 2.029 Cu II 5.0 1 1.5 73Sagl... 

Tetramethyl-2-(6-bromo-2-p)Tidyl)-d -imidazoline-l-oxyl mercury(II)... 

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