Nickel(II) complex of a biradical: Structure, magnetic properties, high NMR temperature sensitivity and moderately fast molecular dynamics

Nickel(II) complex of a biradical: Structure, magnetic properties, high NMR temperature sensitivity and moderately fast molecular dynamics Full article

Journal

Sensors and Actuators B-chemical
ISSN: 0925-4005 , E-ISSN: 1873-3077

Output data

Year: 2017, Volume: 239, Pages: 405-412 Pages count : 8 DOI: 10.1016/j.snb.2016.08.015

Authors

Babailov Sergey P. ^1,2 , Peresypkina Eugenia V. ^1,3 , Journaux Yves ^4,5 , Vostrikova Kira E. ¹

Affiliations

1	Nikolaev Institute of Inorganic Chemistry 3 Lavrentiev avenue, 630090 Novosibirsk, Russian Federation
2	National Research Tomsk Polytechnic University, Lenin Avenue 30, Tomsk 634050, Russian Federation
3	Novosibirsk State University 2 Pirogova str., 630090 Novosibirsk, Russian Federation
4	Sorbonne Universités, UPMC Univ Paris 06, Institut Parisien de Chimie Moléculaire, 4 place Jussieu, 75252 Paris Cedex 05, France
5	CNRS, UMR 8232, Institut Parisien de Chimie Moléculaire, F-75005 Paris, France

A novel nickel(II) complex of a tridentate iminonitroxyl biradical, [Ni(bisimpy)MeOH(ReO4)2], (1) (bisimpy = 2,6-bis(4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazol-2-yl-1-oxyl)pyridine) was structurally and magnetically characterized. Due to an effective separation of the molecules in solid the magnetic behavior of 1 differs considerably from that of a related complex studied earlier, the spin carriers in the former having been strongly ferromagnetically coupled even at room temperature. Dynamic behavior of the paramagnetic cation [Ni(bisimpy)(CD3OD)3]in CD3OD solution was studied by 1H NMR.Atemperature dependence of the spectrum of 1 has been analyzed using a dynamic NMR approach. It was shown that an interconversion of two conformers is liable for a fast dynamic process occurring in solution of 1 at elevated temperatures. An estimated value of G‡(298K) for this process was found to be of 59 ± 3 kJ/mol. It was confirmed that a considerable extension of the measurable rate constants range compared to that for diamagnetic compounds is a result of the paramagnetic chemical shifts in the Ni complex. Application of paramagnetic d-metal complexes as probes for studying ofthe free-energy changes in chemical exchange processes, as well as the advantages of this method compared to diamagnetic species are considered. The investigated complex represents an example of the new type of thermometric NMR sensors being to our knowledge is the most temperature sensitive reagent among the d-metal paramagnetic coordination compounds.

Babailov S.P. , Peresypkina E.V. , Journaux Y. , Vostrikova K.E.
Nickel(II) complex of a biradical: Structure, magnetic properties, high NMR temperature sensitivity and moderately fast molecular dynamics
Sensors and Actuators B-chemical. 2017. V.239. P.405-412. DOI: 10.1016/j.snb.2016.08.015 WOS Scopus РИНЦ OpenAlex

Submitted:	May 30, 2016
Accepted:	Aug 30, 2016
Published online:	Aug 30, 2016
Published print:	Jan 30, 2017

Web of science:	WOS:000388951300050
Scopus:	2-s2.0-84981237521
Elibrary:	26961328
OpenAlex:	W2478546316

DB	Citing
Scopus	28
OpenAlex	29