Tetramethyl Orthosilicate as a Sharp-Selective Catalyst of C3-Methylation of Indole by Supercritical Methanol Full article
| Journal |
The Journal of Supercritical Fluids
ISSN: 0896-8446 , E-ISSN: 1872-8162 |
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| Output data | Year: 2012, Volume: 69, Pages: 82-90 Pages count : 9 DOI: 10.1016/j.supflu.2012.05.013 | ||||||
| Tags | 3-Methylindole, Homogeneous catalysis, Indole methylation, Supercritical methanol, Tetramethyl orthosilicate | ||||||
| Authors |
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| Affiliations |
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Funding (1)
| 1 | Russian Foundation for Basic Research | 11-03-12049 |
Abstract:
Methylation reaction of indole was studied in supercritical methanol (350 °C, 215 atm) catalyzed by TMOS and TEOS. Use of both orthosilicates shows the same result of indole methylation. The indole conversion is ∼30% for 5 h of the reaction with and without catalysts. But catalytic reaction is more high-selective on 3-methyl-1H-indole formation – 95–96 mol% against 60 mol% for non-catalytic methylation. Indole conversion in catalytic reaction increases by a quarter (with no change of selectivity) when two equivalents of water are added into reaction mixture. Methylating system was assumed to be the TMOS–MeOH, and methylation proceeds via cyclic, multi-centered transition state (TS). The TS involves molecules of indole, TMOS, methanol, and water (if used), which are orientated in a certain way to each other by hydrogen and coordinate bonding. The reaction does not occur in supercritical ethanol or isopropanol with and without using the catalysts.
Cite:
Kozhevnikov I.V.
, Nuzhdin A.L.
, Bukhtiyarova G.A.
, Martyanov O.N.
, Chibiryaev A.M.
Tetramethyl Orthosilicate as a Sharp-Selective Catalyst of C3-Methylation of Indole by Supercritical Methanol
The Journal of Supercritical Fluids. 2012. V.69. P.82-90. DOI: 10.1016/j.supflu.2012.05.013 WOS Scopus РИНЦ OpenAlex ANCAN
Tetramethyl Orthosilicate as a Sharp-Selective Catalyst of C3-Methylation of Indole by Supercritical Methanol
The Journal of Supercritical Fluids. 2012. V.69. P.82-90. DOI: 10.1016/j.supflu.2012.05.013 WOS Scopus РИНЦ OpenAlex ANCAN
Dates:
| Submitted: | Mar 9, 2012 |
| Accepted: | May 23, 2012 |
| Published online: | Jun 2, 2012 |
| Published print: | Sep 1, 2012 |
Identifiers:
| ≡ Web of science: | WOS:000307414100011 |
| ≡ Scopus: | 2-s2.0-84863950092 |
| ≡ Elibrary: | 20477417 |
| ≡ OpenAlex: | W1998030343 |
| ≡ Chemical Abstracts: | 2012:1039806 |
| ≡ Chemical Abstracts (print): | 157:467861 |