99052-87-6Relevant academic research and scientific papers
Not Limited to Iron: A Cobalt Heme–NO Model Facilitates N–N Coupling with External NO in the Presence of a Lewis Acid to Generate N2O
Abucayon, Erwin G.,Khade, Rahul L.,Powell, Douglas R.,Zhang, Yong,Richter-Addo, George B.
supporting information, p. 18598 - 18603 (2019/11/14)
Some bacterial heme proteins catalyze the coupling of two NO molecules to generate N2O. We previously reported that a heme Fe–NO model engages in this N?N bond-forming reaction with NO. We now demonstrate that (OEP)CoII(NO) similarly reacts with 1 equiv of NO in the presence of the Lewis acids BX3 (X=F, C6F5) to generate N2O. DFT calculations support retention of the CoII oxidation state for the experimentally observed adduct (OEP)CoII(NO?BF3), the presumed hyponitrite intermediate (P.+)CoII(ONNO?BF3), and the porphyrin π-radical cation by-product of this reaction, and that the π-radical cation formation likely occurs at the hyponitrite stage. In contrast, the Fe analogue undergoes a ferrous-to-ferric oxidation state conversion during this reaction. Our work shows that cobalt hemes are chemically competent to engage in the NO-to-N2O conversion reaction.
Photochemistry of Nitrosyl Porphyrins in the Temperature Range 180-300 K and the Effects of Pyridine on Photodenitrosylation of Nitrosyliron Tetraphenylporphyrin
Hoshino, Mikio,Kogure, Mieko
, p. 5478 - 5484 (2007/10/02)
Nitrosylmetal tetraphenylporphyrin (NOMTPP, M=Fe,Co, and Mn) in benzene solutions undergoes facile photodenitrosylation to give NO and metal(II) tetraphenylporphyrin, MIITPP.The photodenitrosylation yields of NOFeTPP and NOCoTPP are respectively determined as 0.50 +/- 0.05 and 1.0 +/- 0.05 at both excitation wavelengths 355 and 532 nm.The yield, Φ, in toluene is expressed as a function of temperature: Φ = (1 + 1.56 x 10-2 exp(2400/RT))-1 for NOFeTPP and Φ = (1 + 1.02 x 10-6 exp(5200/RT))-1 for NOCoTPP.Contrary to NOFeTPP and NOCoTPP, the photodenitrosylation yields, Φ, of NOMnTPP are independent of temperature in the range 300-180 K and exhibit excitation wavelength dependence: Φ = 0.78 +/- 0.05 at 355 nm and Φ + 0.62 +/- 0.05 at 532 nm.The effects of the central metal on photodenitrosylation are described.The laser photolysis of NOFeTPP in the presence of low concentration of pyridine revealed that the FeIITPP initially produced reacts with a pyridine molecule, Py, to form five-coordinate (Py)FeIITPP.The five-coordinate (Py)Fe%II%TPP further reacts with Py to give six-coordinate (Py)2FeIITPP, which recombines with NO to regenerate NOFeTPP.The kinetic study has demonstrated that the five-coordinate (Py)FeIITPP which is in equilibrium with (Py)2FeIITPP is responsible for the recombination reaction of (Py)2FeIITPP and NO.
Laser Photolysis Studies of Nitric Oxide Adducts of Cobalt(II) Porphyrins. Photoinduced Denitrosylation at the Temperature Range 160-300 K
Hoshino, Mikio,Arai, Shigeyoshi,Yamaji, Minoru,Hama, Yoshimasa
, p. 2109 - 2111 (2007/10/02)
Laser photolysis studies reveal that nitric oxide cobalt(II) porphyrins in 2-methyltetrahydrofuran solutions undergo facile photolytic dissociation to yield nitric oxide and cobalt(II) porphyrin.The quantum yields for the photodissociation of nitric oxide
