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Keisuke Sugita - One of the best experts on this subject based on the ideXlab platform.
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The Catalysis of Vapor-Phase Beckmann Rearrangement for the Production of ε-Caprolactam
Catalysis Surveys from Asia, 2003Co-Authors: Hiroshi Ichihashi, Masaru Kitamura, Masaya Ishida, Akinobu Shiga, Tatsuya Suzuki, Katsuhiro Suenobu, Keisuke SugitaAbstract:Recently, Sumitomo Chemical Co., Ltd. developed the vapor-phase Beckmann Rearrangement process for the production of ε-caprolactam. In the process, cyclohexanone oxime is rearranged into ε-caprolactam using a zeolite as a catalyst instead of sulfuric acid. EniChem in Italy developed the ammoximation process that involves the direct production of cyclohexanone oxime without producing any ammonium sulfate. Sumitomo Chemical Co., Ltd. has commercialized the combined process of vapor-phase Beckmann Rearrangement and ammoximation in 2003. In this paper, the authors focus on some aspects of the vapor-phase Beckmann Rearrangement catalysis. A solid catalyst that is mainly composed of a high-silica MFI zeolite (Silicalite-1) has been developed for the vapor-phase Beckmann Rearrangement. This catalyst does not possess acidity that can be detected by ammonia TPD. Methanol fed into the reactor with cyclohexanone oxime improves the yield of caprolactam. Methanol reacts with terminal silanols on the zeolite surface and converts them to methoxyl groups. The modification of the catalyst by methanol has an important role for the Beckmann Rearrangement reaction. Nest silanols located just inside the pore mouth of the MFI zeolite are supposed to be the active sites of the catalyst. We propose that the coordination between the NOH group of cyclohexanone oxime molecule and the nest silanols through hydrogen bonding is responsible for the reaction. The reaction mechanism of Beckmann Rearrangement under vapor-phase conditions is the same as in the liquid phase, namely, the alkyl group in anti-position against the hydroxyl group of the oxime migrates to the nitrogen atom's position.
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the catalysis of vapor phase Beckmann Rearrangement for the production of e caprolactam
Catalysis Surveys From Asia, 2003Co-Authors: Hiroshi Ichihashi, Masaru Kitamura, Masaya Ishida, Akinobu Shiga, Tatsuya Suzuki, Katsuhiro Suenobu, Keisuke SugitaAbstract:Recently, Sumitomo Chemical Co., Ltd. developed the vapor-phase Beckmann Rearrangement process for the production of e-caprolactam. In the process, cyclohexanone oxime is rearranged into e-caprolactam using a zeolite as a catalyst instead of sulfuric acid. EniChem in Italy developed the ammoximation process that involves the direct production of cyclohexanone oxime without producing any ammonium sulfate. Sumitomo Chemical Co., Ltd. has commercialized the combined process of vapor-phase Beckmann Rearrangement and ammoximation in 2003.
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The Catalysis of Vapor-Phase Beckmann Rearrangement for the Production of ε-Caprolactam
Catalysis Surveys from Asia, 2003Co-Authors: Hiroshi Ichihashi, Masaru Kitamura, Masaya Ishida, Akinobu Shiga, Tatsuya Suzuki, Katsuhiro Suenobu, Keisuke SugitaAbstract:Recently, Sumitomo Chemical Co., Ltd. developed the vapor-phase Beckmann Rearrangement process for the production of e-caprolactam. In the process, cyclohexanone oxime is rearranged into e-caprolactam using a zeolite as a catalyst instead of sulfuric acid. EniChem in Italy developed the ammoximation process that involves the direct production of cyclohexanone oxime without producing any ammonium sulfate. Sumitomo Chemical Co., Ltd. has commercialized the combined process of vapor-phase Beckmann Rearrangement and ammoximation in 2003.
Hiroshi Ichihashi - One of the best experts on this subject based on the ideXlab platform.
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development and industrialization of the vapor phase Beckmann Rearrangement process
Bulletin of the Chemical Society of Japan, 2007Co-Authors: Yoshitaka Izumi, Yasumoto Shimazu, Masaru Kitamura, Hiroshi Ichihashi, Hiroshi SatoAbstract:The development of a new catalyst effective for the vapor-phase Beckmann Rearrangement of cyclohexanone oxime has made it possible to establish a commercial process for the production of e-caprolactam without producing any ammonium sulfate. Through fundamental studies of the catalyst, it was discovered that an MFI-type zeolite composed exclusively of silica had a high selectivity and activity for the vapor-phase Beckmann Rearrangement. Based on acidity measurements and on the reactivity of oximes with different sizes as well as the calculation results of the deprotonation energies of some silanols, we have suggested that the active sites are nest silanols located close to their mouth of the micro pores. By addition of methanol into the reaction system, the selectivity for 8-caprolactam was markedly improved to the levels required for industrialization. A fluidized bed reactor was used for the reaction system in order to maintain a continuous production. By combining the ammoximation process for production of cyclohexanone oxime using the TS-1 catalyst and the vapor-phase Beckmann Rearrangement, a commercial plant has been operating on a 60000 tons per year scale since April 2003, without any troubles.
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The Catalysis of Vapor-Phase Beckmann Rearrangement for the Production of ε-Caprolactam
Catalysis Surveys from Asia, 2003Co-Authors: Hiroshi Ichihashi, Masaru Kitamura, Masaya Ishida, Akinobu Shiga, Tatsuya Suzuki, Katsuhiro Suenobu, Keisuke SugitaAbstract:Recently, Sumitomo Chemical Co., Ltd. developed the vapor-phase Beckmann Rearrangement process for the production of ε-caprolactam. In the process, cyclohexanone oxime is rearranged into ε-caprolactam using a zeolite as a catalyst instead of sulfuric acid. EniChem in Italy developed the ammoximation process that involves the direct production of cyclohexanone oxime without producing any ammonium sulfate. Sumitomo Chemical Co., Ltd. has commercialized the combined process of vapor-phase Beckmann Rearrangement and ammoximation in 2003. In this paper, the authors focus on some aspects of the vapor-phase Beckmann Rearrangement catalysis. A solid catalyst that is mainly composed of a high-silica MFI zeolite (Silicalite-1) has been developed for the vapor-phase Beckmann Rearrangement. This catalyst does not possess acidity that can be detected by ammonia TPD. Methanol fed into the reactor with cyclohexanone oxime improves the yield of caprolactam. Methanol reacts with terminal silanols on the zeolite surface and converts them to methoxyl groups. The modification of the catalyst by methanol has an important role for the Beckmann Rearrangement reaction. Nest silanols located just inside the pore mouth of the MFI zeolite are supposed to be the active sites of the catalyst. We propose that the coordination between the NOH group of cyclohexanone oxime molecule and the nest silanols through hydrogen bonding is responsible for the reaction. The reaction mechanism of Beckmann Rearrangement under vapor-phase conditions is the same as in the liquid phase, namely, the alkyl group in anti-position against the hydroxyl group of the oxime migrates to the nitrogen atom's position.
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the catalysis of vapor phase Beckmann Rearrangement for the production of e caprolactam
Catalysis Surveys From Asia, 2003Co-Authors: Hiroshi Ichihashi, Masaru Kitamura, Masaya Ishida, Akinobu Shiga, Tatsuya Suzuki, Katsuhiro Suenobu, Keisuke SugitaAbstract:Recently, Sumitomo Chemical Co., Ltd. developed the vapor-phase Beckmann Rearrangement process for the production of e-caprolactam. In the process, cyclohexanone oxime is rearranged into e-caprolactam using a zeolite as a catalyst instead of sulfuric acid. EniChem in Italy developed the ammoximation process that involves the direct production of cyclohexanone oxime without producing any ammonium sulfate. Sumitomo Chemical Co., Ltd. has commercialized the combined process of vapor-phase Beckmann Rearrangement and ammoximation in 2003.
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10 Vapor phase Beckmann Rearrangement over a high silica MFI zeolite
Science and Technology in Catalysis 2002 Proceedings of the Fourth Tokyo conference on Advance Catalytic Science and Technology, 2003Co-Authors: Hiroshi IchihashiAbstract:Abstract A catalyst that is mainly composed of a high silica MFI zeolite (Silicalite-1) has been developed for the vapor phase Beckmann Rearrangement of cyclohexanone oxime to ɛ-caprolactam. This catalyst does not possess acidity that can be detected by ammonia TPD. Methanol fed into the reactor with the oxime improves the yield of caprolactam. Methanol reacts with terminal silanols on the zeolite surface at an elevated temperature and converts them to methoxyl groups. The modification of the catalyst by methanol plays an important role in the Beckmann Rearrangement reaction. We consider that the reaction mechanism of Beckmann Rearrangement under vapor phase conditions is the same as in the liquid phase, namely the alkyl group in the anti position against the hydroxyl group of the oxime migrates to the N atom position. Nest silanols located just inside the pore mouth of the MFI zeolite are assumed to be the active sites of the catalyst. We propose that the NOH group of cyclohexanone oxime molecule adsorbed on the zeolite surface is coordinated by OH groups of the nest silanols with hydrogen bonding. This coordination seems to play an important role in the reaction.
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The Catalysis of Vapor-Phase Beckmann Rearrangement for the Production of ε-Caprolactam
Catalysis Surveys from Asia, 2003Co-Authors: Hiroshi Ichihashi, Masaru Kitamura, Masaya Ishida, Akinobu Shiga, Tatsuya Suzuki, Katsuhiro Suenobu, Keisuke SugitaAbstract:Recently, Sumitomo Chemical Co., Ltd. developed the vapor-phase Beckmann Rearrangement process for the production of e-caprolactam. In the process, cyclohexanone oxime is rearranged into e-caprolactam using a zeolite as a catalyst instead of sulfuric acid. EniChem in Italy developed the ammoximation process that involves the direct production of cyclohexanone oxime without producing any ammonium sulfate. Sumitomo Chemical Co., Ltd. has commercialized the combined process of vapor-phase Beckmann Rearrangement and ammoximation in 2003.
Wei-ping Deng - One of the best experts on this subject based on the ideXlab platform.
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Mechanistic Insight into Self-Propagation of Organo-Mediated Beckmann Rearrangement: A Combined Experimental and Computational Study
2016Co-Authors: Boxue Tian, Leif A. Eriksson, Wei-ping DengAbstract:Organo-mediated Beckmann Rearrangement in the liquid phase, which has the advantage of high efficiency and straightforward experimental procedures, plays an important role in the synthesis of amides from oximes. However, the catalytic mechanisms of these organic-based promoters are still not well understood. In this work, we report a combined experimental and computational study on the mechanism of Beckmann Rearrangement mediated by organic-based promoters, using TsCl as an example. A novel self-propagating cycle is proposed, and key intermediates of this self-propagating cycle are confirmed by both experiments and DFT calculations. In addition, the reason why cyclohexanone oxime is not a good substrate of the organo-mediated Beckmann Rearrangement is discussed, and a strategy for improving the yield is proposed
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Catalysts or initiators? Beckmann Rearrangement revisited.
The Journal of organic chemistry, 2013Co-Authors: Boxue Tian, Wei-ping Deng, Leif A. ErikssonAbstract:The catalytic mechanism of the organo-mediated Beckmann Rearrangement has been modeled using DFT calculations. Five representative promoters were shown to be initiators rather than catalysts. A self-propagating mechanism is shown to be energetically much more favored than the previously proposed mechanisms involving a Meisenheimer complex.
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Mechanistic Insight into Self-Propagation of Organo-Mediated Beckmann Rearrangement: A Combined Experimental and Computational Study
The Journal of organic chemistry, 2013Co-Authors: Boxue Tian, Leif A. Eriksson, Wei-ping DengAbstract:Organo-mediated Beckmann Rearrangement in the liquid phase, which has the advantage of high efficiency and straightforward experimental procedures, plays an important role in the synthesis of amides from oximes. However, the catalytic mechanisms of these organic-based promoters are still not well understood. In this work, we report a combined experimental and computational study on the mechanism of Beckmann Rearrangement mediated by organic-based promoters, using TsCl as an example. A novel self-propagating cycle is proposed, and key intermediates of this self-propagating cycle are confirmed by both experiments and DFT calculations. In addition, the reason why cyclohexanone oxime is not a good substrate of the organo-mediated Beckmann Rearrangement is discussed, and a strategy for improving the yield is proposed.
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A Mild and Highly Efficient Catalyst for Beckmann Rearrangement, BF3·OEt2
Chinese Journal of Chemistry, 2011Co-Authors: Li-feng Liu, Wei-ping DengAbstract:BF3·OEt2 (Boron trifluoride etherate), an inexpensive and commercially easily available Lewis acid stoichiometrically employed for Beckamann Rearrangement in general, was now found to efficiently catalyze Beckmann Rearrangement of ketoximes into their corresponding amides (up to 99% yield) in anhydrous acetonitrile under reflux temperature.
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a mild and highly efficient catalyst for Beckmann Rearrangement bf3 oet2
Chinese Journal of Chemistry, 2011Co-Authors: Li-feng Liu, Wei-ping DengAbstract:BF3·OEt2 (Boron trifluoride etherate), an inexpensive and commercially easily available Lewis acid stoichiometrically employed for Beckamann Rearrangement in general, was now found to efficiently catalyze Beckmann Rearrangement of ketoximes into their corresponding amides (up to 99% yield) in anhydrous acetonitrile under reflux temperature.
Khagga Mukkanti - One of the best experts on this subject based on the ideXlab platform.
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Beckmann Rearrangement of oximes using pivaloyl chloride dmf complex
Tetrahedron Letters, 2011Co-Authors: Srinivasa Reddy Narahari, Buchi Reddy Reguri, Khagga MukkantiAbstract:A new complex of pivaloyl chloride and DMF was found to be very effective for converting ketoximes into their corresponding amides or lactams with excellent conversion via the Beckmann Rearrangement. This method offers significant advantages such as efficiency and mild reaction conditions with shorter reaction time.
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Beckmann Rearrangement of oximes using pivaloyl chloride/DMF complex
Tetrahedron Letters, 2011Co-Authors: Srinivasa Reddy Narahari, Buchi Reddy Reguri, Khagga MukkantiAbstract:A new complex of pivaloyl chloride and DMF was found to be very effective for converting ketoximes into their corresponding amides or lactams with excellent conversion via the Beckmann Rearrangement. This method offers significant advantages such as efficiency and mild reaction conditions with shorter reaction time.
Masaru Kitamura - One of the best experts on this subject based on the ideXlab platform.
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development and industrialization of the vapor phase Beckmann Rearrangement process
Bulletin of the Chemical Society of Japan, 2007Co-Authors: Yoshitaka Izumi, Yasumoto Shimazu, Masaru Kitamura, Hiroshi Ichihashi, Hiroshi SatoAbstract:The development of a new catalyst effective for the vapor-phase Beckmann Rearrangement of cyclohexanone oxime has made it possible to establish a commercial process for the production of e-caprolactam without producing any ammonium sulfate. Through fundamental studies of the catalyst, it was discovered that an MFI-type zeolite composed exclusively of silica had a high selectivity and activity for the vapor-phase Beckmann Rearrangement. Based on acidity measurements and on the reactivity of oximes with different sizes as well as the calculation results of the deprotonation energies of some silanols, we have suggested that the active sites are nest silanols located close to their mouth of the micro pores. By addition of methanol into the reaction system, the selectivity for 8-caprolactam was markedly improved to the levels required for industrialization. A fluidized bed reactor was used for the reaction system in order to maintain a continuous production. By combining the ammoximation process for production of cyclohexanone oxime using the TS-1 catalyst and the vapor-phase Beckmann Rearrangement, a commercial plant has been operating on a 60000 tons per year scale since April 2003, without any troubles.
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The Catalysis of Vapor-Phase Beckmann Rearrangement for the Production of ε-Caprolactam
Catalysis Surveys from Asia, 2003Co-Authors: Hiroshi Ichihashi, Masaru Kitamura, Masaya Ishida, Akinobu Shiga, Tatsuya Suzuki, Katsuhiro Suenobu, Keisuke SugitaAbstract:Recently, Sumitomo Chemical Co., Ltd. developed the vapor-phase Beckmann Rearrangement process for the production of ε-caprolactam. In the process, cyclohexanone oxime is rearranged into ε-caprolactam using a zeolite as a catalyst instead of sulfuric acid. EniChem in Italy developed the ammoximation process that involves the direct production of cyclohexanone oxime without producing any ammonium sulfate. Sumitomo Chemical Co., Ltd. has commercialized the combined process of vapor-phase Beckmann Rearrangement and ammoximation in 2003. In this paper, the authors focus on some aspects of the vapor-phase Beckmann Rearrangement catalysis. A solid catalyst that is mainly composed of a high-silica MFI zeolite (Silicalite-1) has been developed for the vapor-phase Beckmann Rearrangement. This catalyst does not possess acidity that can be detected by ammonia TPD. Methanol fed into the reactor with cyclohexanone oxime improves the yield of caprolactam. Methanol reacts with terminal silanols on the zeolite surface and converts them to methoxyl groups. The modification of the catalyst by methanol has an important role for the Beckmann Rearrangement reaction. Nest silanols located just inside the pore mouth of the MFI zeolite are supposed to be the active sites of the catalyst. We propose that the coordination between the NOH group of cyclohexanone oxime molecule and the nest silanols through hydrogen bonding is responsible for the reaction. The reaction mechanism of Beckmann Rearrangement under vapor-phase conditions is the same as in the liquid phase, namely, the alkyl group in anti-position against the hydroxyl group of the oxime migrates to the nitrogen atom's position.
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the catalysis of vapor phase Beckmann Rearrangement for the production of e caprolactam
Catalysis Surveys From Asia, 2003Co-Authors: Hiroshi Ichihashi, Masaru Kitamura, Masaya Ishida, Akinobu Shiga, Tatsuya Suzuki, Katsuhiro Suenobu, Keisuke SugitaAbstract:Recently, Sumitomo Chemical Co., Ltd. developed the vapor-phase Beckmann Rearrangement process for the production of e-caprolactam. In the process, cyclohexanone oxime is rearranged into e-caprolactam using a zeolite as a catalyst instead of sulfuric acid. EniChem in Italy developed the ammoximation process that involves the direct production of cyclohexanone oxime without producing any ammonium sulfate. Sumitomo Chemical Co., Ltd. has commercialized the combined process of vapor-phase Beckmann Rearrangement and ammoximation in 2003.
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The Catalysis of Vapor-Phase Beckmann Rearrangement for the Production of ε-Caprolactam
Catalysis Surveys from Asia, 2003Co-Authors: Hiroshi Ichihashi, Masaru Kitamura, Masaya Ishida, Akinobu Shiga, Tatsuya Suzuki, Katsuhiro Suenobu, Keisuke SugitaAbstract:Recently, Sumitomo Chemical Co., Ltd. developed the vapor-phase Beckmann Rearrangement process for the production of e-caprolactam. In the process, cyclohexanone oxime is rearranged into e-caprolactam using a zeolite as a catalyst instead of sulfuric acid. EniChem in Italy developed the ammoximation process that involves the direct production of cyclohexanone oxime without producing any ammonium sulfate. Sumitomo Chemical Co., Ltd. has commercialized the combined process of vapor-phase Beckmann Rearrangement and ammoximation in 2003.