Mechanistic Insight into Heterogeneous Hydrogenation of Furan Derivatives with the Use of Parahydrogen
Научная публикация
| Общее |
Язык:
Английский,
Жанр:
Статья (Full article),
Статус опубликования:
Опубликована,
Оригинальность:
Оригинальная
|
| Журнал |
ChemCatChem
ISSN: 1867-3880
, E-ISSN: 1867-3899
|
| Вых. Данные |
Год: 2018,
Том: 10,
Номер: 5,
Страницы: 1178-1183
Страниц
: 6
DOI:
10.1002/cctc.201701653
|
| Ключевые слова |
Hydrogenation, Oxygen heterocycles, Polarization, Reaction mechanisms, Supported catalysts |
| Авторы |
Salnikov Oleg G.
1,2
,
Kovtunova Larisa M.
2,3
,
Skovpin Ivan V.
1,2
,
Bukhtiyarov Valerii I.
2,3
,
Kovtunov Kirill V.
1,2
,
Koptyug Igor V.
1,2
|
| Организации |
| 1 |
Laboratory of Magnetic Resonance Microimaging International Tomography Center, SB RAS 3A Institutskaya st., Novosibirsk 630090, Russia
|
| 2 |
Novosibirsk State University 2 Pirogova st., Novosibirsk 630090, Russia
|
| 3 |
Laboratory of Surface Science Boreskov Institute of Catalysis, SB RAS 5 Acad. Lavrentiev pr., Novosibirsk 630090, Russia
|
|
Информация о финансировании (4)
|
1
|
Федеральное агентство научных организаций России
|
0303-2016-0004
|
|
2
|
Российский научный фонд
|
17-73-20030
|
|
3
|
Российский фонд фундаментальных исследований
|
16-33-60198
|
|
4
|
Федеральное агентство научных организаций России
|
0333-2017-0002
|
Parahydrogen-induced polarization (PHIP) was shown to be a useful and unique technique for mechanistic studies of catalytic reactions involving hydrogen. In this paper, PHIP was utilized for mechanistic investigation of gas phase hydrogenation of furan, 2,3-dihydrofuran and 2,5-dihydrofuran over titania-supported Rh, Pd and Pt catalysts. In hydrogenations of all three substrates over Rh/TiO2 catalysts, PHIP technique revealed the possibility of pairwise addition of two H atoms from the same H2 molecule with formation of tetrahydrofuran molecules while retaining spin correlation between added protons. In hydrogenation of 2,3-dihydrofuran over Rh/TiO2 catalysts, PHIP effects were detected not only for tetrahydrofuran but also for the reactant (2,3-dihydrofuran) at positions 2 and 3 of heterocyclic ring. Such unexpected results are a direct evidence of the occurrence of pairwise replacement of hydrogen atoms in 2,3-dihydorfuran. The probable mechanism of this pairwise replacement includes the sequential steps of addition and elimination of hydrogen atoms. In contrast, when hydrogenation of 2,5-dihydrofuran was carried out over Rh/TiO2, PHIP effects were detected for all protons of 2,3-dihydrofuran, implying that 2,3-dihydrofuran can be formed from 2,5-dihydrofuran not only via isomerization of C=C bond but also via dehydrogenation of 2,5-dihydrofuran to furan with subsequent semihydrogenation.