Dynamic polarization chemically induced

Kaptein R and Oosterhoff J L 1969 Chemically Induced dynamic polarization II (relation with anomalous ESR spectra) Chem. Phys. Lett. 4 195-7... 

G. R. Lawler, Chemically Induced Dynamic Polarization (CIDNP). II. The Radical-Pair Model," Accfs. Chem. Res. 5, 25 (1972). 

The technique most recently introduced to study radical cations is chemically induced dynamic polarization (CIDNP), a nuclear resonance method based on the observation of transient signals, substantially enhanced in either absorption or emission. These effects are induced as a result of magnetic interactions in radical or radical ion pairs on the nanosecond timescale. This method requires acquisition of an NMR spectrum during (or within a few seconds of) the generation of the radical ion pairs. The CIDNP technique is applied in solution, typically at room... 

I. P. Beletskaya, V. S. Rykov and A. L. Buchachenko, Internal Symposium on Chemically Induced Dynamic Polarization of Nuclei and Electrons, Tallin, 1972, Abstr., p. 16. 

The altered NMR spectra characteristic of chemically induced dynamic polarization (CIDNP) (22) are observed during the photo-lytic decomposition of various peroxides in the presence of photosensitizers at ambient temperatures, as well as the thermal decomposition of these peroxides in the absence of light at temperatures where they have a short half-life. The reactions which are responsible for CIDNP are apparently similar in both cases. 

Bargon, J., The Discovery of Chemically Induced Dynamic Polarization (CIDNP), Helv. Chim. Acta 2006, 89, 2082 2102. 

Chemically induced dynamic polarization has been observed in the presence of [Eu(fod)3] and [Pr(fod)3]. 

Lawler R G 1967 Chemically Induced dynamic nuclear polarization J. Am. Chem. Soc. 89 5519-21... 

Goez M 1995 An introduction to chemically induced dynamic nuclear polarization Concepts Magn. Reson. 7 69-86... 

Kaptein R 1971 Simple rules for chemically induced dynamic nuclear polarization J. Chem. See. Chem. Commun. 732-3... 

Morozova O B, Tsentalovich Y P, Yurkovskaya A V and Sagdeev R Z 1998 Consecutive biradicals during the photolysis of 2,12-dihydroxy-2,12-dimethylcyclododecanone low- and high-field chemically induced dynamic nuclear polarizations (CIDNP) study J. Rhys. Chem. A 102 3492-7... 

Pedersen J B and Freed J H 1973 Theory of chemically induced dynamic electron polarization. I J. 

Wong S K, Hutchinson D A and Wan J K S 1973 Chemically induced dynamic electron polarization. II. A general theory for radicals produced by photochemical reactions of excited triplet carbonyl compounded. Chem. Phys. 58 985-9... 

Carboxamides, formation from ArNj 243 2-Carboxybenzenediazonium zwitterion, see 2-Diazoniobenzenecarboxylate Carboxy-de-diazoniation 241 f. Carcinogenicity 319 Chemically induced dynamic nuclear polarization, see CIDNP Chloro-de-diazoniation 194, 230ff., 247, 270, 277... 

CIDNP chemically induced dynamic nuclear polarization... 

CHEMICALLY INDUCED DYNAMIC NUCLEAR SPIN POLARIZATION AND ITS APPLICATIONS... 

VI. Chemically Induced Dynamic Electron Spin Polarization (CIDBP)... 

The first reports of the observation of transient emission and enhanced absorption signals in the H-n.m.r. spectra of solutions in which radical reactions were taking place appeared in 1967. The importance of the phenomenon, named Chemically Induced Dynamic Nuclear Spin Polarization (CIDNP), in radical chemistry was quickly recognized. Since that time, an explosive growth in the number of publications on the subject has occurred and CIDNP has been detected in H, C, N, and P as well as H-n.m.r. spectra. Nevertheless, the number of groups engaged in research in this area is comparatively small. This may be a consequence of the apparent complexity of the subject. It is the purpose of this review to describe in a quahtative way the origin of CIDNP and to survey the published applications of the phenomenon in... 

Kaptein, R. (1971b). Chemically Induced Dynamic Nuclear Polarization , Thesis, Leiden. 

Chemically Induced Dynamic Nuclear Polarization Complete Neglect of Differential Overlap cyclopentadienyl diethyl azodicarboxylate... 

Observation of spin-polarized products resulting from these radical pairs by the method of chemically induced dynamic nuclear polarization (CIDNP)<67) was accomplished by photolysis in the probe of an NMR spectrometer using perfluoromethylcyclohexane as solvent. The results obtained were consistent with nuclear spin polarization steps involving radical pairs formed from dissociated radicals and also directly from excited states, although the former could not be detected in carbon tetrachloride, probably due to radical scavenging by the solvent. It was not possible to determine the fraction of the reaction proceeding by singlet and triplet radical pairs.<68)... 

Chain processes, free radical, in aliphatic systems involving an electron transfer reaction, 23,271 Charge density-NMR chemical shift correlation in organic ions, 11,125 Chemically induced dynamic nuclear spin polarization and its applications, 10, 53 Chemiluminescence of organic compounds, 18,187... 

The chemically induced dynamic nuclear polarization (DNP) opened perspective to study products formed from free radicals [102], The basis of this study is the difference in NMR spectra of normal molecules and those formed from free radicals and radical pairs. The molecules formed from radicals have an abnormal NMR spectrum with lines of emission and abnormal absorption [102]. DNP spectra help to obtain the following mechanistic information ... 

On the other hand, in accord with the free radical mechanism peroxynitrite is dissociated into free radicals, which are supposed to be genuine reactive species. Although free radical mechanism was proposed as early as in 1970 [111], for some time it was not considered to be a reliable one because a great confusion ensued during the next two decades because of misinterpretations of inconclusive experiments, sometimes stimulated by improper thermodynamic estimations [85]. The latest experimental data supported its reliability [107-109]. Among them, the formation of dityrosine in the reaction with tyrosine and 15N chemically induced dynamic nuclear polarization (CIDNP) in the NMR spectra of the products of peroxynitrite reactions are probably the most convincing evidences (see below). 

Finally, Podoplelov and coworkers41 have prepared trimethyltin hydride and benzyltrimethyltin labelled with tin-117 from a tin sample enriched to 92% in 117Sn. The photochemical reaction between dibenzyl ketone and trimethyltin-117 hydride was used to investigate the chemically induced dynamic nuclear polarization of tin-containing radicals. 

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