Angewandte Chemie International Edition in English
Direct conversion of inert alkanes into carbonyl-containing organic compounds is an important goa... more Direct conversion of inert alkanes into carbonyl-containing organic compounds is an important goal for industrial organic chemistry. Alkanes can be carbonylated into carboxylic acids or aldehydes in superacidic HF/SbF 5 or CF 3 SO 3 H/SbF 5 systems. [1] However, environmental concerns require the use of more environmentally friendly solid catalysts. The strong acidity and exceptionally high activity of sulfated zirconia [2] (SZ) means it has received much attention as a potential catalyst for hydrocarbon conversion, [3] and especially for overcoming the chemical inertness of alkanes. The direct carbonylation of benzene with CO using a pure SZ as the solid acid catalyst has been reported recently. [4] However, saturated hydrocarbons were never reported to be involved in carbon-ylation reactions on SZ, only the inhibiting effect of carbon monoxide on linear alkane isomerization with SZ has been demonstrated. [5] Herein we report direct 13 C solid-state NMR spectroscopic measurements o...
Elsevier journal. The attached copy is furnished to the author for non-commercial research and ed... more Elsevier journal. The attached copy is furnished to the author for non-commercial research and education use, including for instruction at the author's institution, sharing with colleagues and providing to institution administration. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright Abstract Hydrogen (H/D) exchange between Brønsted acid sites of both the acidic form of zeolite beta (H-BEA) and Zn-loaded zeolite beta (Zn/H-BEA) and small alkanes (methane and ethane) has been studied by monitoring the kinetics of the exchange in situ with 1 H MAS NMR spectroscopy w...
journal published by Elsevier. The attached copy is furnished to the author for internal non-comm... more journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit:: Acid-form and Zn-and Ga-modified zeolite BEA Acidic silanol groups 1 H MAS NMR IR spectroscopy a b s t r a c t Acidic OH groups of acid-form and Zn and Ga-modified zeolite beta (BEA) have been characterized with 1 H MAS NMR and by IR spectroscopy of adsorbed carbon monoxide. It is demonstrated that OH groups, which exhibit a vibration band ...
By using in situ13C MAS NMR and ex situ GC-MS, the analysis of hydrocarbon products formed from n... more By using in situ13C MAS NMR and ex situ GC-MS, the analysis of hydrocarbon products formed from n-octene-1 adsorbed on sulfated zirconia catalyst (SZ) has been performed. It is shown that a mixture of alkanes and stable alkyl substituted cyclopentenyl cations (CPC) is formed as the basic reaction products. Formation of both alkanes and CPC from n-octene-1, a precursor of C8+ cation, the key intermediate in n-butane isomerization via a “bimolecular pathway”, implies that formation of the isomerized alkane occurs by a complex process of “conjunct polymerization”, rather than isomerization itself. CPC deposited on the SZ surface can be in charge of the catalyst deactivation.
Angewandte Chemie International Edition in English
Direct conversion of inert alkanes into carbonyl-containing organic compounds is an important goa... more Direct conversion of inert alkanes into carbonyl-containing organic compounds is an important goal for industrial organic chemistry. Alkanes can be carbonylated into carboxylic acids or aldehydes in superacidic HF/SbF 5 or CF 3 SO 3 H/SbF 5 systems. [1] However, environmental concerns require the use of more environmentally friendly solid catalysts. The strong acidity and exceptionally high activity of sulfated zirconia [2] (SZ) means it has received much attention as a potential catalyst for hydrocarbon conversion, [3] and especially for overcoming the chemical inertness of alkanes. The direct carbonylation of benzene with CO using a pure SZ as the solid acid catalyst has been reported recently. [4] However, saturated hydrocarbons were never reported to be involved in carbon-ylation reactions on SZ, only the inhibiting effect of carbon monoxide on linear alkane isomerization with SZ has been demonstrated. [5] Herein we report direct 13 C solid-state NMR spectroscopic measurements o...
Elsevier journal. The attached copy is furnished to the author for non-commercial research and ed... more Elsevier journal. The attached copy is furnished to the author for non-commercial research and education use, including for instruction at the author's institution, sharing with colleagues and providing to institution administration. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright Abstract Hydrogen (H/D) exchange between Brønsted acid sites of both the acidic form of zeolite beta (H-BEA) and Zn-loaded zeolite beta (Zn/H-BEA) and small alkanes (methane and ethane) has been studied by monitoring the kinetics of the exchange in situ with 1 H MAS NMR spectroscopy w...
journal published by Elsevier. The attached copy is furnished to the author for internal non-comm... more journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit:: Acid-form and Zn-and Ga-modified zeolite BEA Acidic silanol groups 1 H MAS NMR IR spectroscopy a b s t r a c t Acidic OH groups of acid-form and Zn and Ga-modified zeolite beta (BEA) have been characterized with 1 H MAS NMR and by IR spectroscopy of adsorbed carbon monoxide. It is demonstrated that OH groups, which exhibit a vibration band ...
By using in situ13C MAS NMR and ex situ GC-MS, the analysis of hydrocarbon products formed from n... more By using in situ13C MAS NMR and ex situ GC-MS, the analysis of hydrocarbon products formed from n-octene-1 adsorbed on sulfated zirconia catalyst (SZ) has been performed. It is shown that a mixture of alkanes and stable alkyl substituted cyclopentenyl cations (CPC) is formed as the basic reaction products. Formation of both alkanes and CPC from n-octene-1, a precursor of C8+ cation, the key intermediate in n-butane isomerization via a “bimolecular pathway”, implies that formation of the isomerized alkane occurs by a complex process of “conjunct polymerization”, rather than isomerization itself. CPC deposited on the SZ surface can be in charge of the catalyst deactivation.
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