Article
Chemistry, Organic
Yan-Long Zheng, Omid Daneshfar, Jia-Yi Li, Jeanne Masson-Makdissi, Emile Pinault-Masson, Stephen G. Newman
Summary: This study developed a transesterification method using Ni/dcype catalyst for the conversion of methyl esters with aliphatic alcohols. The reaction cleaves the strong C(acyl)-OMe bond in the absence of acidic or basic additives, generating only volatile methanol as the waste product. A wide range of (hetero)aromatic and aliphatic methyl esters can be efficiently converted into functionalized esters. Compared to traditional transesterifications, this cross-coupling approach offers new opportunities for efficient and chemoselective synthesis.
Article
Biochemistry & Molecular Biology
Noreen Sajjad, Raha Orfali, Shagufta Perveen, Sabiha Rehman, Aeysha Sultan, Taslim Akhtar, Arif Nazir, Gulzar Muhammad, Tahir Mehmood, Safina Ghaffar, Areej Al-Taweel, Muhammad Jilani, Munawar Iqbal
Summary: Biodiesel is a sustainable alternative to petro-diesel, but the use of costly edible oils as raw materials increases production costs, hindering its economic feasibility. This study explores the use of non-edible oils as raw materials and optimizes reaction conditions for biodiesel production using Tamarindus indica seed oil. The results show that Tamarindus indica could be a potential and viable option for large-scale biodiesel production, replacing petro-diesel.
Article
Chemistry, Physical
Xiuru Bi, Nan Yao, Xu Meng, Mingxia Gou, Peiqing Zhao
Summary: MnCO3 was found to be an efficient heterogeneous catalyst for transesterification of alcohols with DMC, giving desired products under mild conditions. MnCO3 calcined at 300 degrees C showed significantly enhanced surface area and abundant weak acid sites, contributing to its superior catalytic performance in the transesterification process.
Article
Chemistry, Multidisciplinary
Jennifer Noro, Joana Cabo, David S. Freitas, Catarina S. Roque, Mariana de Castro, Artur Cavaco-Paulo, Carla Silva
Summary: In this study, three deep eutectic mixtures (DES) were used as mediums to synthesize glucose laurate and glucose acetate. Lipases from Aspergillus oryzae (LAO), Candida rugosa (LCR), and porcine pancreas (LPP) were employed as catalysts. The results showed that DES did not deactivate the lipases when used as medium. For transesterification reactions, combining LAO or LCR with DES 3 resulted in efficient production of glucose laurate, while LPP performed best in DES 2 for glucose acetate synthesis. Substituting vinyl laurate with vinyl acetate led to different behaviors, with LCR and LPP showing better catalytic activity in DES 1 for glucose acetate production. LAO had lower activity, with only around 40% product yield in DES 3. These findings highlight the potential of biocatalysis combined with greener solvents for the synthesis of differentiated sugar fatty acid esters.
Review
Chemistry, Physical
Iqra Riaz, Iqrash Shafiq, Farrukh Jamil, Ala'a H. Al-Muhtaseb, Parveen Akhter, Sumeer Shafique, Young-Kwon Park, Murid Hussain
Summary: This article provides a review of various catalysts used in biodiesel production, with a focus on naturally derived heterogeneous catalysts. It explores the use of different heterogeneous catalysts as alternatives to homogeneous catalysts for the esterification and transesterification of nonedible and low-cost biomasses. The article also analyzes the impact and long-term performance of biodiesel in various applications, and reports advancements in catalysts and processes to facilitate further development in biodiesel production.
CATALYSIS REVIEWS-SCIENCE AND ENGINEERING
(2022)
Article
Energy & Fuels
Zongwu Xin, Guangtao Wei, Linye Zhang, Lei Gao, Zhongmin Li, Weiran Zhao
Summary: This work introduced a new method of partially hydrogenating FAMEs using sodium borohydride as hydrogen donor and Ni-La-B as catalyst to upgrade biodiesel. Under optimum conditions, high conversion ratio and good hydrogenation effect were achieved.
Article
Energy & Fuels
Ricardo Garcia-Morales, Abel Zunigo-Moreno, Francisco J. Veronico-Sanchez, Jose Domenzain-Gonzalez, Hugo I. Perez-Lopez, Christian Bouchot, Octavio Elizalde-Solis
Summary: The aim of this study was to synthesize fatty acid methyl esters from waste beef tallow using one-step supercritical methanol transesterification without pre-treatment. Animal waste samples were collected from local markets and experiments were conducted in a batch reactor made of Inconel 625 alloy. Various parameters such as methanol:waste beef tallow molar ratio, temperature, and pressure were investigated to obtain the fatty acid methyl esters, which were then characterized and the overall yield was calculated.
Article
Chemistry, Multidisciplinary
Grecia K. Sanchez-Munoz, Marina A. Ortega-Rojas, Leticia Chavelas-Hernandez, Rodrigo S. Razo-Hernandez, Jonathan R. Valdez-Camacho, Jaime Escalante
Summary: Recent progress in the catalytic promiscuity of enzymes has led to the increased use of biocatalysis in organic chemistry. This paper presents a versatile biocatalytic method for the synthesis of benzyl esters through a transesterification reaction using Candida antarctica lipase B (CaLB) and benzyl alcohol in the absence of solvent. The effect of nucleophile size and the substituent attached to the carbonyl group was also studied.
Article
Polymer Science
Celeste Libretti, Michael A. R. Meier
Summary: In this study, direct transesterification of cellulose was achieved and cellulose esters with different degrees of substitution were successfully synthesized. The obtained cellulose esters exhibited good thermal stability, UV absorption, and antioxidant properties. Additionally, the switchable solvent system demonstrated excellent recyclability.
Article
Multidisciplinary Sciences
Baoxin Zhang, Christoph Kubis, Robert Franke
Summary: This study reports the stable performance of unmodified cobalt carbonyl catalyst at lower syngas pressures and without phosphorus ligands at lower temperatures. The catalyst showed comparable activity to other coordinated cobalt catalysts and exhibited high regioselectivity.
Article
Chemistry, Multidisciplinary
Yue Hu, Shiyun Zhang, Juanfang Xu, Yuan Liu, Aiai Yu, Jun Qian, Yinjun Xie
Summary: The study demonstrates an efficient strategy for degrading diverse waste polyesters at low temperature and pressure, utilizing a quinaldine-based Ru complex for initial transesterification and hydrogenation. The catalysts can be hydrogenated to an active species, which shows strong viability and high activity in protic solvent. Methanol plays a crucial role in promoting reaction efficiency throughout the process.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Materials Science, Paper & Wood
Stephanie C. Hernandez, Romain Milotskyi, Shohei Takagi, Elisabeth R. D. Ito, Shiori Suzuki, Naoki Wada, Kenji Takahashi
Summary: Cellulose mixed esters (CMEs) with tunable properties are difficult to produce due to the insolubility of cellulose. A rapid and scalable production method of CMEs was demonstrated using a twin-screw extruder as a flow reactor. By using a co-solvent system and continuous extrusion, cellulose acetate propionate (CAP) was obtained within minutes with high conversion rates.
Article
Chemistry, Physical
Jie Qi Ng, Hiro Arima, Takuya Mochizuki, Kohei Toh, Kai Matsui, Manussada Ratanasak, Jun-Ya Hasegawa, Manabu Hatano, Kazuaki Ishihara
Summary: A highly chemoselective transesterification catalyzed by NaOAr or Mg(OAr)2 was developed, allowing for the production of functionalized acrylates without undesired Michael additions under mild reaction conditions. Computational density functional theory calculations supported the high chemoselectivity of this reaction.
Article
Chemistry, Multidisciplinary
Yan-Long Zheng, Pei-Pei Xie, Omid Daneshfar, Kendall N. Houk, Xin Hong, Stephen G. Newman
Summary: A new method has been developed to convert alkyl esters into alkyl ketones, resulting in the synthesis of 65 different alkyl ketones with various functional groups and heterocyclic structures. The study found that catalyst-controlled chemoselectivity could activate the C(acyl)-O bond in the substrate, while density functional theory calculations supported the mechanism of the nickel catalytic cycle.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Engineering, Environmental
Gang Wang, Xiaoming Hu, Shirun Zhao
Summary: An innovative liquid-phase catalytic system was developed for the direct synthesis of methyl methacrylate (MMA) from methyl propionate and methanol. The new system addressed the issues of poor selectivity, rapid catalyst deactivation, and formaldehyde polymerization that occurred in the traditional one-step aldol reaction. The yield and selectivity of MMA reached up to 50.2% and 81.8% at mild conditions of 60 degrees C and 1 atm.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Dimitrije Djukanovic, Maximilian A. Ganiek, Kohei Nishi, Konstantin Karaghiosoff, Kazushi Mashima, Paul Knochel
Summary: A new convenient method for the preparation of dicarbamoylzincs is reported in this study. The target compounds were obtained by reacting ZnCl2 and formamides or TMP2Zn with formamides. This method is compatible with sensitive functional groups such as esters, ketones, or nitro groups. The reaction of these dicarbamoylzincs with various functionalized allylic, benzylic, aryl, alkenyl compounds, acid chlorides, aldehydes, or enones resulted in the synthesis of polyfunctional amides in high yields. The C-13 NMR characterization of these new compounds is presented.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Daiki Kato, Tomoya Murase, Jalindar Talode, Haruki Nagae, Hayato Tsurugi, Masahiko Seki, Kazushi Mashima
Summary: This study demonstrates the selective synthesis of multifunctionalized ketones using copper salts and aryl Grignard reagents. The method shows good tolerance towards various functional groups and can be applied to the synthesis of important synthetic intermediates.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Darryl F. Nater, Christoph J. Kaul, Lukas Laetsch, Hayato Tsurugi, Kazushi Mashima, Christophe Coperet
Summary: Tailored molybdenum (VI)-oxo complexes can catalyze olefin metathesis reaction under specific conditions, and the structural, spectroscopic and electronic characteristics of the catalyst precursor have an influence on the initiation and catalytic efficiency of the final product.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Physical
Koichi Shinohara, Hayato Tsurugi, Kazushi Mashima
Summary: In this study, a novel lanthanum amide complex was reported as an efficient catalyst for the N-methylation of N-alkylaniline derivatives with CO2 in the presence of PhSiH3. Experimental and computational investigations revealed the crucial role of multiple noncovalent interactions in the reaction mechanism.
Article
Chemistry, Multidisciplinary
Kohei Nishi, Hayato Tsurugi, Kazushi Mashima
Summary: Chromium-catalyzed olefination of aryl aldehydes with haloforms using 2,3,5,6-tetramethyl-N,N'-bis(trimethylsilyl)-1,4-dihydropyrazine (1a) as an organic reducing agent leads to trans-selective formation of beta-halostyrene derivatives. This reaction eliminates the need for metal powders such as zinc and manganese as reductants, reducing metal-based reaction waste.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Tomomi Kawakami, Sota Tamaki, Satoru Shirase, Hayat o Tsurugi, Kazushi Mashima
Summary: A hexanuclear Ce(IV) cluster bridged by oxo and hydroxo groups was synthesized and found to exhibit strong absorption in the ultraviolet A to blue light region. Irradiation with blue LED light induced a chemical reaction, resulting in the formation of a new compound. This study is of great significance for understanding the properties and potential applications of this cluster.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Yohei Ueda, Hayato Tsurugi, Kazushi Mashima
Summary: Cobalt-catalyzed hydroalkynylation of alkynes, alkenes, and imines allows for the synthesis of internal alkynes with various functional groups adjacent to the carbon-carbon triple bond in an atom-economical manner. In addition, cross-coupling reactions using alkynylcobalt species generated in situ from terminal alkynes, haloalkynes, and metal acetylides selectively provide internal aryl and alkylalkynes.
Article
Chemistry, Physical
Kosuke Higashida, Valentin Smail, Haruki Nagae, Jean-Francois Carpentier, Kazushi Mashima
Summary: We successfully achieved nickel(0)-catalyzed asymmetric allylic alkylation (AAA) of beta-dicarbonyl compounds under ambient conditions by activating unstrained C-C bonds of 2-allylated 2-methylcyclohexane-1,3-dione derivatives. The reaction produced quaternary chiral compounds with high yield and enantioselectivity. The mechanism of the AAA reaction with the Ni(0)-(S)-tol-MeO-BIPHEP catalyst system was elucidated through control experiments and DFT calculations.
Review
Chemistry, Multidisciplinary
Takanori Iwasaki, Nobuaki Kambe
Summary: Carbon-fluorine bonds are stable but can be selectively transformed under appropriate conditions, making them useful synthetic methods in organic chemistry. This review focuses on C-C bond formation at monofluorinated sp(3)-hybridized carbons via C-F bond cleavage, including cross-coupling and multi-component coupling reactions. The mechanisms of C-F bond cleavage on sp(3)-hybridized carbon centers are categorized into three types: Lewis acids promoted F atom elimination, nucleophilic substitution with metal or carbon nucleophiles, and cleavage of C-F bonds via single electron transfer. Furthermore, the unique characteristics of alkyl fluorides compared to other (pseudo)halides as electrophilic coupling counterparts are discussed.
Article
Multidisciplinary Sciences
Takanori Iwasaki, Kazuki Tsuge, Naoki Naito, Kyoko Nozaki
Summary: This study reports an Ir catalyst for the selective hydrogenolysis of urea derivatives, achieving the transformation of less reactive carbonyl compounds in the presence of more reactive ones. The proposed catalyst showed tolerance to highly reactive carbonyl groups such as ester, amide, and carbamate, and exhibited high chemoselectivity towards urea. This research provides a new strategy for the chemical recycling of polyurea resins.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Kohei Nishi, Hayato Tsurugi, Kazushi Mashima
Summary: Chromium(III) trichloride combined with aryl/alkyl Grignard reagents showed high catalytic activity for the synthesis of syn-2-aryl/alkyl-1,2-dihydronaphthalen-1-ols through the ring-opening aryl/alkylation of 7-oxabenzonorbornadiene derivatives. The chromium catalyst allowed the use of unstable aryl Grignard reagents with esters and N-protecting groups. In situ formed diarylchromate(I) from tetraarylchromate(III) was identified as the active species in this catalytic reaction based on control experiments.
Article
Chemistry, Multidisciplinary
Haruki Nagae, Saki Matsushiro, Jun Okuda, Kazushi Mashima
Summary: We discovered that a cationic hetero tetranuclear complex with a calcium and three cobalt ions demonstrated high catalytic activity for the alternating copolymerization of propylene oxide (PO) and carbon dioxide (CO2). The tertiary anilinium salt [PhNMe2H][B(C6F5)(4)] was identified as the best additive to generate the cationic species and maintain polymer selectivity and carbonate linkage, even at 1.0 MPa CO2. Density functional theory calculations revealed that the reaction pathway mediated by the cationic complex is more favorable than that mediated by the neutral complex, with an energy difference of 1.0 kcal mol(-1). Additionally, we found that the exchange of flexible ligands between calcium and cobalt ions is crucial for the smooth proceeding of the alternating copolymerization.
Article
Chemistry, Physical
Kohei Nishi, Hayato Tsurugi, Kazushi Mashima
Summary: Chromium(III) trichloride in combination with aryl/alkyl Grignard reagents exhibited high catalytic activity for the ring-opening arylation reaction of 7-oxabenzonorbornadiene derivatives, producing syn-2-aryl/alkyl-1,2-dihydronaphthalen-1-ols in high yields. The superior catalytic activity of the chromium catalyst allowed the use of unstable aryl Grignard reagents. Control experiments suggested that the in situ formed diarylchromate(I) served as the active species in the catalytic reaction.
Article
Chemistry, Physical
Kosuke Higashida, Valentin Smail, Haruki Nagae, Jean-Francois Carpentier, Kazushi Mashima
Summary: We achieved a nickel(0)-catalyzed asymmetric allylic alkylation reaction of beta-dicarbonyl compounds under ambient conditions, resulting in high yields of quaternary chiral compounds with high enantioselectivity.
Article
Chemistry, Physical
Takanori Iwasaki, Wataru Ishiga, Shrinwantu Pal, Kyoko Nozaki, Nobuaki Kambe
Summary: This study reports the mechanistic investigation of the Rh-catalyzed cross-coupling reaction between vinylic ethers and aryl Grignard reagents. The presence of olefinic ligands significantly affects the catalytic activity of Rh precatalysts. Computational studies reveal that the reaction proceeds through Mg cation-assisted insertion/anti-beta-oxygen elimination, with the Mg countercation coordinating to the ethereal oxygen atom in the transition state.
