Aurophilic Interactions in Multi‐Radical Species: Electronic‐Spin and Redox Properties of Bis‐ and Tris‐[(Nitronyl Nitroxide)‐Gold(I)] Complexes with Phosphine‐Ligand Scaffolds

Verdazyl-nitroxide diradicals were synthesized using the palladium-catalyzed cross-coupling reaction of the corresponding iodoverdazyls with a nitronyl nitroxide-2-ide gold(I) complex with high yields (up to 82%). The synthesized diradicals were found to be highly thermally stable and have a singlet (DEST » -64 cm–1) or triplet ground state (DEST ³ 25 and 100 cm–1), depending on which canonical hydrocarbon diradical type they belong to. Upon crystallization, triplet diradicals form unique one-dimensional (1D) spin S = 1 chains of organic diradicals with intrachain ferromagnetic coupling of J′/kB from 3 to 6 K.

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Faculty Opinions recommendation of Redox properties of human transferrin bound to its receptor.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1008023.201963 ◽

2004 ◽

Author(s):

Edward Stiefel

Keyword(s):

Redox Properties ◽

Human Transferrin

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Kinetics of the Thermal Disappearance of Radicals Formed During the Radiolysis of Aspartic Acid

Revista de Chimie ◽

10.37358/rc.08.12.2067 ◽

2009 ◽

Vol 59 (12) ◽

Author(s):

Mihai Contineanu ◽

iulia Contineanu ◽

Ana Neacsu ◽

Stefan Perisanu

Keyword(s):

Thermal Resistance ◽

Aspartic Acid ◽

Room Temperature ◽

Esr Spectra ◽

Complex Mechanism ◽

Radical Species ◽

Mechanisms Of Formation ◽

Kinetics Of

The radiolysis of the isomers L-, D- and DL- of the aspartic acid, in solid polycrystalline state, was investigated at room temperature. The analysis of their ESR spectra indicated the formation of at least two radicalic entities. The radical, identified as R3, resulting from the deamination of the acid, exhibits the highest concentration and thermal resistance. Possible mechanisms of formation of three radical species are suggested, based also on literature data. The kinetics of the disappearance of radical R3 indicated a complex mechanism. Three possible variants were suggested for this mechanism.

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Polymer oxidation catalyst containing acidic functional groups

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19811237 ◽

1981 ◽

Vol 46 (5) ◽

pp. 1237-1247

Author(s):

Zdeněk Prokop ◽

Karel Setínek

Keyword(s):

Functional Groups ◽

Elevated Temperatures ◽

Redox Properties ◽

Oxidation Catalyst ◽

Carbon Clusters ◽

Oxidation Activity ◽

Redox Sites ◽

Styrene Divinylbenzene ◽

Proportional Decrease ◽

Polymer Oxidation

The catalyst containing redox sites in addition to acid functional groups was prepared by sulphonation of a macroporous chloromethylated styrene-divinylbenzene copolymer with concentrated sulphuric acid at elevated temperatures. Its activity was tested for the oxidation of 2-propanol by molecular oxygen at 120 °C and was found to be comparable to that of the iridium on carbon catalyst.Neutralisation of acid functional groups by alkali metal led to proportional decrease in the oxidation activity. The results of EPR spectroscopic study of these catalysts show that the redox properties of the polymer are caused by carbon clusters which are capable of electron exchange.

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