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Ricardo Da Silva Sercheli - One of the best experts on this subject based on the ideXlab platform.
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Conversão catalitica de oleo de pinus em alcoois terpenicos, usados como fragrancias e aromas
2017Co-Authors: Ricardo Da Silva SercheliAbstract:Resumo: Atualmente, o linalol é obtido a partir de extratos de pineno seguindo a sequência: hidrogenação, oxidação na presença de um iniciador radicalar para o hidroperóxido correspondente, e redução através de um processo estequiométrico. O álcool formado é então pirolisado para linalol. Neste projeto, estudou-se a otimização da rota de síntese do linalol, substituindo as etapas de oxidação e redução por um sistema catalítico que leva diretamente ao álcool. As reações de redução de a- e b-pineno foram conduzidas à pressão ambiente e sob pressão de hidrogênio; essas reações à pressão ambiente foram realizadas em um Schlenk, utilizando-se ácido acético como solvente e Pd/C 5% como catalisador; obtiveram-se como produtos cis- e trans-pinano, com uma relação molar de 1:1. Por outro lado, nas reações realizadas sob 50 atm de H2, em um reator de aço inox a 25°C, obtêve- se seletividade de 80% para cis-pinano. Em ambos os casos, as conversões foram de até 98%. As reações de oxidação catalítica foram realizadas em um balão da três bocas, equipado com um borbulhador (adição de oxigênio através de uma placa porosa), termômetro e um condensador de refluxo...OBS.: O resumo na integra poderá ser visualizado no link ou texto completo da tese digitalAbstract: At present, linalool is obtained from Pinene extracts following the sequence: hydrogenation, oxidation in the presence of a radical initiator to the corresponding hydroperoxide, followed by reduction in a stoichiometric process. The alcohol formed is then pyrolysed to linalool. In this project, the optimization of linalool synthesis was investigated, substituting the oxidation and reduction steps by a catalytic system, which leads directly to the alcohol. The reduction reactions of a- and b-Pinene were carried out at 1 and 50 atm of H2. The reactions at atmospheric pressure were carried out in a Schlenk, using acetic acid as solvent, and 5% Pd/C as the catalyst; giving cis- and trans-pinane (1:1) as the products. On the other hand, for the reactions carried out at 50 atm of H2, in a steel reactor, at 25°C, a selectivity of 80% for cis-pinane was obtained. In both cases, the conversions were up to 98%. The catalytic oxidation reactions were carried out in a three necked flask, equipped with a gas inlet tube (addition of oxygen trhough a glass frit), thermometer and a reflux condenser. ..Note: the complete abstract is avaiable with the link or full eletrocin digital theses or dissertations
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Conversão catalitica de oleo de pinus em alcoois terpenicos, usados como fragrancias e aromas
Universidade Estadual de Campinas. Instituto de Química, 1996Co-Authors: Ricardo Da Silva SercheliAbstract:Atualmente, o linalol é obtido a partir de extratos de pineno seguindo a sequência: hidrogenação, oxidação na presença de um iniciador radicalar para o hidroperóxido correspondente, e redução através de um processo estequiométrico. O álcool formado é então pirolisado para linalol. Neste projeto, estudou-se a otimização da rota de síntese do linalol, substituindo as etapas de oxidação e redução por um sistema catalítico que leva diretamente ao álcool. As reações de redução de a- e b-pineno foram conduzidas à pressão ambiente e sob pressão de hidrogênio; essas reações à pressão ambiente foram realizadas em um Schlenk, utilizando-se ácido acético como solvente e Pd/C 5% como catalisador; obtiveram-se como produtos cis- e trans-pinano, com uma relação molar de 1:1. Por outro lado, nas reações realizadas sob 50 atm de H2, em um reator de aço inox a 25°C, obtêve- se seletividade de 80% para cis-pinano. Em ambos os casos, as conversões foram de até 98%. As reações de oxidação catalítica foram realizadas em um balão da três bocas, equipado com um borbulhador (adição de oxigênio através de uma placa porosa), termômetro e um condensador de refluxo...OBS.: O resumo na integra poderá ser visualizado no link ou texto completo da tese digitalAt present, linalool is obtained from Pinene extracts following the sequence: hydrogenation, oxidation in the presence of a radical initiator to the corresponding hydroperoxide, followed by reduction in a stoichiometric process. The alcohol formed is then pyrolysed to linalool. In this project, the optimization of linalool synthesis was investigated, substituting the oxidation and reduction steps by a catalytic system, which leads directly to the alcohol. The reduction reactions of a- and b-Pinene were carried out at 1 and 50 atm of H2. The reactions at atmospheric pressure were carried out in a Schlenk, using acetic acid as solvent, and 5% Pd/C as the catalyst; giving cis- and trans-pinane (1:1) as the products. On the other hand, for the reactions carried out at 50 atm of H2, in a steel reactor, at 25°C, a selectivity of 80% for cis-pinane was obtained. In both cases, the conversions were up to 98%. The catalytic oxidation reactions were carried out in a three necked flask, equipped with a gas inlet tube (addition of oxygen trhough a glass frit), thermometer and a reflux condenser. ..Note: the complete abstract is avaiable with the link or full eletrocin digital theses or dissertations
Congxia Xie - One of the best experts on this subject based on the ideXlab platform.
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synthesis of magnetic ru fe3o4 c nanospheres with controlled carbon layer and its high selectivity to prepare cis pinane
Chemical Engineering Journal, 2016Co-Authors: Yue Liu, Congxia Xie, Shiwei LiuAbstract:Abstract A magnetic Ru/Fe3O4@C catalyst was prepared by loading Ru nanoparticles on a controller carbon layer. The characterization results showed that Ru/Fe3O4@C with the core-shell structured microspheres had good superparamagnetic properties and that the introduction of the controlled carbon layer adsorbent improved the morphological regularity, monodispersity and size uniformity of the Ru nanoparticles. The Ru/Fe3O4@C catalyst demonstrated a high catalytic activity towards the hydrogenation of α-Pinene to form cis-pinane. The conversion of α-Pinene was 99.3% and the selectivity for cis-pinane reached 98.2% at 160 °C for 2 h. The Ru/Fe3O4@C catalyst was easily separated from the reaction mixture when applying an external magnetic field, and the separated Ru/Fe3O4@C had a good reusability. After being reused 10 times, the α-Pinene conversion and the cis-pinane selectivity decreased to 97.6% and 97.1%, respectively.
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synthesis of silanized magnetic ru fe3o4 sio2 nanospheres and their high selectivity to prepare cis pinane
RSC Advances, 2016Co-Authors: Yue Liu, Shiwei Liu, Congxia XieAbstract:(3-Aminopropyl)-triethoxysilane (APTS) and (3-mercaptopropyl)-trimethoxysilane (MPTS) grafted SiO2-coated iron oxide (Fe3O4@SiO2) magnetic supports were prepared. Various noble metal nanoparticles such as Ru, Pt, Rh and Pd were directly grown on the surfaces of the magnetic supports with ultrasmall and nearly monodisperse sizes, especially the APTS grafted Fe3O4@SiO2 (Fe3O4@SiO2/APTS) nanospheres. The Fe3O4@SiO2/APTS/Ru catalyst demonstrated a high catalytic activity towards the hydrogenation of α-Pinene to form cis-pinane. The conversion of α-Pinene was 99.1% and the selectivity for cis-pinane reached 97.6% at 120 °C after 4 h. The Fe3O4@SiO2/APTS/Ru catalyst was easily separated from the reaction mixture when applying an external magnetic field, and the separated Fe3O4@SiO2/APTS/Ru had good reusability. After being reused eight times, the α-Pinene conversion and the cis-pinane selectivity also can reach 97.8% and 96.9%, respectively.
Shiwei Liu - One of the best experts on this subject based on the ideXlab platform.
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synthesis of magnetic ru fe3o4 c nanospheres with controlled carbon layer and its high selectivity to prepare cis pinane
Chemical Engineering Journal, 2016Co-Authors: Yue Liu, Congxia Xie, Shiwei LiuAbstract:Abstract A magnetic Ru/Fe3O4@C catalyst was prepared by loading Ru nanoparticles on a controller carbon layer. The characterization results showed that Ru/Fe3O4@C with the core-shell structured microspheres had good superparamagnetic properties and that the introduction of the controlled carbon layer adsorbent improved the morphological regularity, monodispersity and size uniformity of the Ru nanoparticles. The Ru/Fe3O4@C catalyst demonstrated a high catalytic activity towards the hydrogenation of α-Pinene to form cis-pinane. The conversion of α-Pinene was 99.3% and the selectivity for cis-pinane reached 98.2% at 160 °C for 2 h. The Ru/Fe3O4@C catalyst was easily separated from the reaction mixture when applying an external magnetic field, and the separated Ru/Fe3O4@C had a good reusability. After being reused 10 times, the α-Pinene conversion and the cis-pinane selectivity decreased to 97.6% and 97.1%, respectively.
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synthesis of silanized magnetic ru fe3o4 sio2 nanospheres and their high selectivity to prepare cis pinane
RSC Advances, 2016Co-Authors: Yue Liu, Shiwei Liu, Congxia XieAbstract:(3-Aminopropyl)-triethoxysilane (APTS) and (3-mercaptopropyl)-trimethoxysilane (MPTS) grafted SiO2-coated iron oxide (Fe3O4@SiO2) magnetic supports were prepared. Various noble metal nanoparticles such as Ru, Pt, Rh and Pd were directly grown on the surfaces of the magnetic supports with ultrasmall and nearly monodisperse sizes, especially the APTS grafted Fe3O4@SiO2 (Fe3O4@SiO2/APTS) nanospheres. The Fe3O4@SiO2/APTS/Ru catalyst demonstrated a high catalytic activity towards the hydrogenation of α-Pinene to form cis-pinane. The conversion of α-Pinene was 99.1% and the selectivity for cis-pinane reached 97.6% at 120 °C after 4 h. The Fe3O4@SiO2/APTS/Ru catalyst was easily separated from the reaction mixture when applying an external magnetic field, and the separated Fe3O4@SiO2/APTS/Ru had good reusability. After being reused eight times, the α-Pinene conversion and the cis-pinane selectivity also can reach 97.8% and 96.9%, respectively.
Yue Liu - One of the best experts on this subject based on the ideXlab platform.
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synthesis of magnetic ru fe3o4 c nanospheres with controlled carbon layer and its high selectivity to prepare cis pinane
Chemical Engineering Journal, 2016Co-Authors: Yue Liu, Congxia Xie, Shiwei LiuAbstract:Abstract A magnetic Ru/Fe3O4@C catalyst was prepared by loading Ru nanoparticles on a controller carbon layer. The characterization results showed that Ru/Fe3O4@C with the core-shell structured microspheres had good superparamagnetic properties and that the introduction of the controlled carbon layer adsorbent improved the morphological regularity, monodispersity and size uniformity of the Ru nanoparticles. The Ru/Fe3O4@C catalyst demonstrated a high catalytic activity towards the hydrogenation of α-Pinene to form cis-pinane. The conversion of α-Pinene was 99.3% and the selectivity for cis-pinane reached 98.2% at 160 °C for 2 h. The Ru/Fe3O4@C catalyst was easily separated from the reaction mixture when applying an external magnetic field, and the separated Ru/Fe3O4@C had a good reusability. After being reused 10 times, the α-Pinene conversion and the cis-pinane selectivity decreased to 97.6% and 97.1%, respectively.
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synthesis of silanized magnetic ru fe3o4 sio2 nanospheres and their high selectivity to prepare cis pinane
RSC Advances, 2016Co-Authors: Yue Liu, Shiwei Liu, Congxia XieAbstract:(3-Aminopropyl)-triethoxysilane (APTS) and (3-mercaptopropyl)-trimethoxysilane (MPTS) grafted SiO2-coated iron oxide (Fe3O4@SiO2) magnetic supports were prepared. Various noble metal nanoparticles such as Ru, Pt, Rh and Pd were directly grown on the surfaces of the magnetic supports with ultrasmall and nearly monodisperse sizes, especially the APTS grafted Fe3O4@SiO2 (Fe3O4@SiO2/APTS) nanospheres. The Fe3O4@SiO2/APTS/Ru catalyst demonstrated a high catalytic activity towards the hydrogenation of α-Pinene to form cis-pinane. The conversion of α-Pinene was 99.1% and the selectivity for cis-pinane reached 97.6% at 120 °C after 4 h. The Fe3O4@SiO2/APTS/Ru catalyst was easily separated from the reaction mixture when applying an external magnetic field, and the separated Fe3O4@SiO2/APTS/Ru had good reusability. After being reused eight times, the α-Pinene conversion and the cis-pinane selectivity also can reach 97.8% and 96.9%, respectively.
Adalberto Manoel Da Silva - One of the best experts on this subject based on the ideXlab platform.
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essential oils from schinus terebinthifolius leaves chemical composition and in vitro cytotoxicity evaluation
Pharmaceutical Biology, 2012Co-Authors: Jeferson S Santana, Patricia Sartorelli, Rafael C Guadagnin, Marisi G Soares, Adalberto Manoel Da Silva, Alisson L Matsuo, Carlos R Figueiredo, Joao Henrique G LagoAbstract:Context: In folk medicine, Schinus terebinthifolius Raddi (Anacardiaceae), has been used as a remedy for ulcers, respiratory problems, wounds, rheumatism, gout, diarrhea, skin ailments and arthritis, as well as to treat tumors and leprosy.Objective: To investigate the chemical composition and cytotoxicity of essential oil from leaves of S. terebinthifolius as well as the identification of active compounds from this oil.Material and methods: Essential oil from S. terebinthifolius leaves, obtained by hydrodistillation using a Clevenger-type apparatus, was characterized in terms of its chemical composition. Also, the crude oil was subjected to chromatographic separation procedures to afford an active fraction composed of α- and β-Pinenes. These compounds, including hydrogenation (pinane) and epoxydation (α-Pinene oxide) derivatives from α-Pinene, were tested in vitro against murine melanoma cell line (B16F10-Nex2) and human melanoma (A2058), breast adenocarcinoma (MCF7), leukemia (human leukemia (HL-60) and ...
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in vitro trypanocidal evaluation of pinane derivatives from essential oils of ripe fruits from schinus terebinthifolius raddi anacardiaceae
Química Nova, 2012Co-Authors: Patricia Sartorelli, Jefferson Santos Santana, Rafael C Guadagnin, Joao Henrique G Lago, Erika G Pinto, Andre G Tempone, Helio A Stefani, Marisi G Soares, Adalberto Manoel Da SilvaAbstract:Essential oils of ripe fruits from Schinus terebinthifolius (Anacardiaceae), obtained using a pilot extractor and a Clevenger apparatus were chemically characterized. Due the high amount of (-)- α-Pinene in both oils, this monoterpene was tested against the protozoan parasite Trypanosoma cruzi, showing a moderate potential (IC50 63.56 µg/mL) when compared to benznidazole (IC50 43.14 µg/mL). Otherwise, (-)- α-Pinene oxide did not showed anti-trypanosomal activity (IC50 > 400 µg/mL) while (-)-pinane showed an IC50 of 56.50 µg/mL. The obtained results indicated that the epoxydation of α-Pinene results to the loss of the anti-parasitic activity while its hydrogenation product, contributed slightly to the increased activity.
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In vitro trypanocidal evaluation of pinane derivatives from essential oils of ripe fruits from Schinus terebinthifolius Raddi (Anacardiaceae)
'FapUNIFESP (SciELO)', 2012Co-Authors: Sartorelli Patrícia, Guadagnin, Rafael Carlos, Lago, João Henrique Ghilardi, Pinto, Erika Gracielle, Stefani, Helio Alexandre, Soares, Marisi Gomes, Santana, Jefferson Santos, Tempone, André Gustavo, Adalberto Manoel Da SilvaAbstract:Essential oils of ripe fruits from Schinus terebinthifolius (Anacardiaceae), obtained using a pilot extractor and a Clevenger apparatus were chemically characterized. Due the high amount of (-)- α-Pinene in both oils, this monoterpene was tested against the protozoan parasite Trypanosoma cruzi, showing a moderate potential (IC50 63.56 µg/mL) when compared to benznidazole (IC50 43.14 µg/mL). Otherwise, (-)- α-Pinene oxide did not showed anti-trypanosomal activity (IC50 > 400 µg/mL) while (-)-pinane showed an IC50 of 56.50 µg/mL. The obtained results indicated that the epoxydation of α-Pinene results to the loss of the anti-parasitic activity while its hydrogenation product, contributed slightly to the increased activity.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo (UNIFESP) Instituto de Ciências Ambientais, Químicas e FarmacêuticasUniversidade de São Paulo Instituto de Medicina Tropical de São PauloInstituto Adolfo Lutz Departamento de ParasitologiaUniversidade de São Paulo Faculdade de Ciências Farmacêuticas Departamento de FarmáciaUniversidade Federal de Alfenas Instituto de QuímicaUniversidade Federal de Viçosa Departamento de QuímicaUNIFESP, Instituto de Ciências Ambientais, Químicas e FarmacêuticasSciEL
