TY - JOUR

T1 - Spin Order Transfer from a Parahydrogen Molecule to a Cyanide Ion in the Iridium Complex under the SABRE Conditions

AU - Zlobina, V. V.

AU - Spiridonov, K. A.

AU - Nikovskii, I. A.

AU - Peregudov, A. S.

AU - Kiryutin, A. S.

AU - Yurkovskaya, A. V.

AU - Polezhaev, A. A.

AU - Novikov, V. V.

N1 - This work was supported by the Russian Science Foundation (interdisciplinary projects nos. 20-63-47107 and 20-62-47038). Elemental analysis of the synthesized compounds was carried out using the equipment of the Center for Molecule Composition Studies at the Nesmeyanov Institute of Organoelement Compounds (Russian Academy of Sciences) and supported by the Ministry of Science and Higher Education of the Russian Federation. Публикация для корректировки.

PY - 2023/8

Y1 - 2023/8

N2 - A possibility of generating a high degree of spin polarization of 13C and 15N nuclei in the cyanide ion, which forms the coordination bond with the metal ion, using parahydrogen is demonstrated for the first time for the new iridium carbene complex as an example. The spin–spin interaction constants in the synthesized complex and the structure of the hydride intermediate are determined by an analysis of the 13С NMR spectra detected using broadband and selective heteronuclear decoupling. The cyanide ion is shown to coordinate to the metal ion by the carbon atom in one of two equatorial positions, and two pyridine molecules are arranged in the axial and equatorial positions. The signal amplification factors for 13С and 15N nuclei of the cyanide anion (5665 and –49 555, respectively) are estimated by NMR spectroscopy of the polarized substrate using the SABRE method from an ultralow magnetic field of 0.5 μT. This amplification corresponds to 15.5% polarization of nitrogen nuclei achieved within several seconds at room temperature.

AB - A possibility of generating a high degree of spin polarization of 13C and 15N nuclei in the cyanide ion, which forms the coordination bond with the metal ion, using parahydrogen is demonstrated for the first time for the new iridium carbene complex as an example. The spin–spin interaction constants in the synthesized complex and the structure of the hydride intermediate are determined by an analysis of the 13С NMR spectra detected using broadband and selective heteronuclear decoupling. The cyanide ion is shown to coordinate to the metal ion by the carbon atom in one of two equatorial positions, and two pyridine molecules are arranged in the axial and equatorial positions. The signal amplification factors for 13С and 15N nuclei of the cyanide anion (5665 and –49 555, respectively) are estimated by NMR spectroscopy of the polarized substrate using the SABRE method from an ultralow magnetic field of 0.5 μT. This amplification corresponds to 15.5% polarization of nitrogen nuclei achieved within several seconds at room temperature.

KW - NMR spectroscopy

KW - carbene ligands

KW - hyperpolarization

KW - iridium complexes

KW - parahydrogen

KW - parahydrogen-induced nuclear hyperpolarization

KW - signal enhancement

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85168658151&origin=inward&txGid=cb12b92923418c664908a914df8b60b3

UR - https://www.mendeley.com/catalogue/c59a0f0d-f86e-3702-9ffb-b3458b6eb5f4/

U2 - 10.1134/S1070328423600444

DO - 10.1134/S1070328423600444

M3 - Article

VL - 49

SP - 471

EP - 478

JO - Russian Journal of Coordination Chemistry/Koordinatsionnaya Khimiya

JF - Russian Journal of Coordination Chemistry/Koordinatsionnaya Khimiya

SN - 1070-3284

IS - 8

ER -