Heterogeneous Hydrogenation of Phenylalkynes with Parahydrogen: Hyperpolarization, Reaction Selectivity, and Kinetics
Science article
| Общее |
Language:
Английский,
Genre:
Full article,
Status:
Published,
Source type:
Original
|
| Journal |
PCCP: Physical Chemistry Chemical Physics
ISSN: 1463-9076
, E-ISSN: 1463-9084
|
| Output data |
Year: 2019,
Volume: 21,
Number: 48,
Pages: 26477-26482
Pages count
: 6
DOI:
10.1039/c9cp02913c
|
| Tags |
LIQUID-PHASE HYDROGENATION; INDUCED POLARIZATION; Pd-NANOPARTICLES; NMR; CATALYSTS; ACETYLENE; EFFICIENT |
| Authors |
Pokochueva Ekaterina V.
1,2
,
Kovtunov Kirill V.
1,2
,
Salnikov Oleg G.
1,2
,
Gemeinhardt Max E.
3
,
Kovtunova Larisa M.
2,4
,
Bukhtiyarov Valerii I.
4
,
Chekmenev Eduard Y.
5,6
,
Goodson Boyd M.
3,7
,
Koptyug Igor V.
1,2
|
| Affiliations |
| 1 |
International Tomography Center SB RAS, 3A Institutskaya St., Novosibirsk, 630090, Russia
|
| 2 |
Novosibirsk State University, 2 Pirogova St., Novosibirsk, 630090, Russia
|
| 3 |
Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, IL 62901, USA
|
| 4 |
Boreskov Institute of Catalysis SB RAS, 5 Acad. Lavrentiev Pr., Novosibirsk, 630090, Russia
|
| 5 |
Department of Chemistry, Integrative Biosciences (Ibio), Wayne State University, Karmanos Cancer Institute (KCI), Detroit, MI 48202, USA
|
| 6 |
Russian Academy of Sciences, 14 Leninskiy Pr., Moscow, 119991, Russia
|
| 7 |
Materials Technology Center, Southern Illinois University, Carbondale, IL 62901, USA
|
|
Funding (7)
|
1
|
National Science Foundation
|
CHE-1416432
|
|
2
|
National Science Foundation
|
CHE-1836308
|
|
3
|
Russian Foundation for Basic Research
|
18-33-20019 (АААА-А18-118101090008-1)
|
|
4
|
Federal Agency for Scientific Organizations
|
0333-2016-0002 (АААА-А16-116121510087-5)
|
|
5
|
Russian Foundation for Basic Research
|
18-43-543023 (АААА-А18-118060990008-2)
|
|
6
|
Russian Science Foundation
|
19-13-00172
|
|
7
|
National Science Foundation
|
CHE-1904780
|
Parahydrogen-induced polarization (PHIP) is a powerful technique for studying hydrogenation reactions in gas and liquid phases. Pairwise addition of parahydrogen to the hydrogenation substrate imparts nuclear spin order to reaction products, manifested as enhanced 1H NMR signals from the nascent proton sites. Nanoscale metal catalysts immobilized on supports comprise a promising class of catalysts for producing PHIP effects; however, on such catalysts the percentage of substrates undergoing the pairwise addition route - a necessary condition for observing PHIP - is usually low. In this paper, we present a systematic study of several metal catalysts (Rh, Pt, Pd, and Ir) supported on TiO2 in liquid-phase hydrogenation of different prototypical phenylalkynes (phenylacetylene, 1-phenyl-1-propyne, and 3-phenyl-1-propyne) with parahydrogen. Catalyst activity and selectivity were found to be affected by both the nature of the active metal and the percentage of metal loading. It was demonstrated that the optimal catalyst for production of hyperpolarized products is Rh/TiO2 with 4 wt% metal loading, whereas Pd/TiO2 provided the greatest selectivity for semihydrogenation of phenylalkynes. In a study of liquid-phase hydrogenation reaction kinetics, it was shown that reaction order with respect to hydrogen is nearly the same for pairwise and non-pairwise H2 addition - consistent with a similar nature of the catalytically active sites for these reaction pathways. This journal is © the Owner Societies.