Research output: Contribution to journal › Article › peer-review
Net Enhanced1H NMR Signals in Symmetric Molecules Produced via Heterogeneous Hydrogenation with Parahydrogen over Immobilized Metal Complexes. / Babenko, S. V.; Skovpin, I. V.; Burueva, D. B. et al.
In: Analytical Chemistry, Vol. 97, No. 38, 2025, p. 20843-20849.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Net Enhanced1H NMR Signals in Symmetric Molecules Produced via Heterogeneous Hydrogenation with Parahydrogen over Immobilized Metal Complexes
AU - Babenko, S. V.
AU - Skovpin, I. V.
AU - Burueva, D. B.
AU - Mustafin, N. R.
AU - Chukanov, N. V.
AU - Kovtunova, L. M.
AU - Koptyug, I. V.
N1 - Net Enhanced1H NMR Signals in Symmetric Molecules Produced via Heterogeneous Hydrogenation with Parahydrogen over Immobilized Metal Complexes / S. V. Babenko, I. V. Skovpin, D. B. Burueva, N. R. Mustafin, N. V. Chukanov, L. M. Kovtunova, I. V. Koptyug // Analytical Chemistry. - 2025. - Т. 97. № 38. - С. 20843-20849
PY - 2025
Y1 - 2025
N2 - Heterogeneous parahydrogen-induced polarization (PHIP) offers a pathway to generate pure hyperpolarized molecular agents devoid of toxic catalysts. While conventional hydrogenative PHIP relies on hydrogenation with parahydrogen (p-H2) and breaking the equivalence of the p-H2-derived protons in the hydrogenation product, spontaneous net polarization is sometimes observed in symmetric systems. In this study, we explore a previously unreported case of net PHIP polarization in symmetric products of heterogeneous hydrogenation reactions in both gas and liquid phases. In particular, the effect was observed for ethylene and orthohydrogen (o-H2) produced in the heterogeneous hydrogenation reactions of acetylene and dimethyl acetylenedicarboxylate (DMAD), respectively, over an immobilized iridium-based catalyst complex. This polarized signal is amplified significantly under continuous-wave radiofrequency irradiation. By comparing these findings to a previously reported net polarization in dimethyl maleate obtained in a homogeneous hydrogenation reaction, we propose that asymmetric relaxation due to cross-correlation between chemical shift anisotropy (CSA) and dipolar coupling or between different dipolar couplings, which was suggested earlier for the homogeneous case, represents one of the possible mechanisms that could drive this phenomenon.
AB - Heterogeneous parahydrogen-induced polarization (PHIP) offers a pathway to generate pure hyperpolarized molecular agents devoid of toxic catalysts. While conventional hydrogenative PHIP relies on hydrogenation with parahydrogen (p-H2) and breaking the equivalence of the p-H2-derived protons in the hydrogenation product, spontaneous net polarization is sometimes observed in symmetric systems. In this study, we explore a previously unreported case of net PHIP polarization in symmetric products of heterogeneous hydrogenation reactions in both gas and liquid phases. In particular, the effect was observed for ethylene and orthohydrogen (o-H2) produced in the heterogeneous hydrogenation reactions of acetylene and dimethyl acetylenedicarboxylate (DMAD), respectively, over an immobilized iridium-based catalyst complex. This polarized signal is amplified significantly under continuous-wave radiofrequency irradiation. By comparing these findings to a previously reported net polarization in dimethyl maleate obtained in a homogeneous hydrogenation reaction, we propose that asymmetric relaxation due to cross-correlation between chemical shift anisotropy (CSA) and dipolar coupling or between different dipolar couplings, which was suggested earlier for the homogeneous case, represents one of the possible mechanisms that could drive this phenomenon.
UR - https://www.mendeley.com/catalogue/12c84c22-49be-3d89-89bd-0df985a4ce3d/
UR - https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=105017372951&origin=inward
U2 - 10.1021/acs.analchem.5c02855
DO - 10.1021/acs.analchem.5c02855
M3 - Article
C2 - 40968109
VL - 97
SP - 20843
EP - 20849
JO - Analytical Chemistry
JF - Analytical Chemistry
SN - 0003-2700
IS - 38
ER -
ID: 70299937