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
Yuse Kuriyama, Yusuke Sasano, Yoshihiko Hoshino, Shun-ichiro Uesugi, Aoto Yamaichi, Yoshiharu Iwabuchi
Summary: Highly regioselective intramolecular aminolysis of 3,4-epoxy amines has been achieved by chemoselective activation of epoxides in the presence of unprotected aliphatic amines in the same molecules using a La(OTf)(3) catalyst, resulting in excellent regioselectivity for anti-Baldwin 5-endo-tet cyclization and stereospecific formation of 3-hydroxy-2-alkylpyrrolidines in high yields. DFT calculations suggested that regioselectivity is attributed to distortion energies of epoxy amine substrates. This reaction was used in the enantioselective synthesis of an antispasmodic agent prifinium bromide.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Thermodynamics
Joon-Hyuk Yim, Hyun Ji Kim, Jai June Oh, Jong Sung Lim, Kyu Yong Choi
Summary: Isobaric vapor-liquid equilibrium data for two binary systems were measured and thermodynamic consistency was assessed using two activity coefficient models. The results support validity of the models used in this study.
FLUID PHASE EQUILIBRIA
(2021)
Article
Food Science & Technology
Yanjun Guo, Yuanbo Zhang, Ruijie Liu, Ming Chang, Jianhua Huang, Xiaosan Wang
Summary: This study discussed the effects of Fe3+, chloride compounds, NaCl, and water on the formation of 3-MCPD and 2-MCPD esters, as well as the concentration ratio between the two. The results showed that MgCl2 had the most significant impact on the formation of the esters, while the concentration of 3-MCPD and 2-MCPD esters in frying oil was proportional to the content of Fe3+. Additionally, the isomer ratio was strongly dependent on frying time and the addition of NaCl and water.
Article
Chemistry, Multidisciplinary
Guoping Yang, Ke Li, Xiaoling Lin, Yijin Li, Chengxing Cui, Shixiong Li, Yuanyuan Cheng, Yufeng Liu
Summary: This study presents an environmentally friendly and sustainable reaction using the catalyst H3PMo12O40 to facilitate the regio- and stereoselective synthesis of (Z)-3-ylidenephthalides from 2-acylbenzoic acids and alcohols. The reaction demonstrates ease of scalability, easy derivatization of products for drug and bioactive compound synthesis, and reveals the importance of appropriate acid catalyst for selectivity in this transformation.
CHINESE JOURNAL OF CHEMISTRY
(2021)
Article
Biochemistry & Molecular Biology
Jiahui Kong, Haijian Xia, Renbao He, Hao Chen, Yongping Yu
Summary: A novel method for synthesizing the key dolutegravir intermediate is described using MgBr2-promoted intramolecular cyclization, resulting in a highly selective conversion process with excellent yield.
Article
Agricultural Engineering
Tayyab Islam, Thuan Phu Nguyen-Vo, Vivek Kumar Gaur, Junhak Lee, Sunghoon Park
Summary: The production of 1,3-butanediol from glucose was achieved by engineering a pathway in Escherichia coli and optimizing gene expression levels and culture conditions. The highest ever reported titer of 1,3-butanediol in biological production methods was achieved at 257 mM in 36 hours with a yield of 0.51 mol/mol. This study provides a promising strategy for sustainable synthesis of other acetyl-CoA-derived chemicals using microbial cell factories.
BIORESOURCE TECHNOLOGY
(2023)
Article
Chemistry, Physical
Xiucan Jia, Yong Luo, Xiaopo Wang
Summary: This study measured the solubility of HFO1243zf in [HMIM][PF6] and [OMIM][PF6], and correlated the experimental data using appropriate models. The mixing thermodynamic properties of R1243zf + [HMIM][PF6] and R1243zf + [OMIM][PF6] solutions were computed, and the dissolving performances of different HFOs were compared and analyzed.
JOURNAL OF MOLECULAR LIQUIDS
(2022)
Article
Chemistry, Physical
Xiucan Jia, Yutian Ma, Xiaopo Wang
Summary: In this study, the vapor-liquid equilibrium of 3, 3, 3-Trifluoropropene (R1243zf) with [Emim][BF4] and [Bmim][BF4] ionic liquids was measured, and the experimental results were correlated using the NRTL model. The effects of different anions and cations on the liquid phase molar fraction of R1243zf were studied. In addition, thermodynamic properties and phase behavior of different HFO refrigerants with [Emim][BF4] were compared and analyzed.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Article
Chemistry, Physical
Satoshi Sato, Ryo Kobayashi, Enggah Kurniawan, Yasuhiro Yamada
Summary: Vapor-phase dehydration of 3-methyl-1,3-butanediol to produce isoprene was investigated using Y2Zr2O7 catalysts prepared by hydrothermal aging at 200 degrees C. The aging process removed residual species and crystallized Y2Zr2O7. X-ray diffraction analysis confirmed the growth of Y2Zr2O7 crystals during hydrothermal aging up to 24 hours. The acid-base properties and catalytic performance of the catalysts were significantly influenced by the hydrothermal aging time.
MOLECULAR CATALYSIS
(2023)
Article
Chemistry, Physical
Shiori Suzuki, Shimon Kurachi, Naoki Wada, Kenji Takahashi
Summary: A facile and sustainable method using an ionic liquid was developed for selectively modifying aliphatic hydroxy groups in Kraft lignin. The two-step homogeneous reaction resulted in high purity selectively modified Kraft lignin with improved yield and repeatability. The modified Kraft lignin showed good solubility, heat-meltability, and thermal stability comparable to completely acetylated lignin.
Article
Biochemistry & Molecular Biology
Xiao-Lin Wang, Ji-Teng Chen, Sheng-Cai Zheng, Xiao-Ming Zhao
Summary: The utilization of 6,6-dimethyl-3-((trimethylsilyl)oxy)cyclohex-2-en-1-one, derived from an unsymmetrical 4,4-dimethylcyclohexane-1,3-dione, in iridium-catalyzed allylic enolization is achieved under mild conditions. The presence of a quaternary carbon and adjustment of reaction conditions enable high selectivities in terms of chemoselectivity, regioselectivity, and enantioselectivity. This method provides substituted 2-(but-3-en-2-yl)-3-hydroxy-6,6-dimethylcyclohex-2-en-1-ones in good to high yields with excellent chemo-, regio-, and enantioselectivities. Additionally, the formation of chiral carbon-fluorine bonds is induced by an adjacent chiral carbon center.
Article
Chemistry, Multidisciplinary
Parvin Salehi, Zahra Tanbakouchian, Noushin Farajinia-Lehi, Morteza Shiri
Summary: A new reaction system was developed utilizing arylsulfonyl methyl isocyanides as both the sulfonyl source and 1,3-dipolar reagent to synthesize the target product through a cascade reaction. This system was successfully facilitated under specific conditions.
Article
Chemistry, Organic
Fei-Fei Liang, Kai-Xuan Liu, Cong Zhao, Zhi-Hao Shang, Hong-Mei Kong, Ya-Qing Yin, Yan-Ping Zhu, Yuan-Yuan Sun, Jian-Wen Yao
Summary: An oxidative [3+1+1] convergent domino cyclization method was developed for the efficient synthesis of various 2,4,5-trisubstituted oxazoles. This method features a wide substrate scope, mild reaction conditions, and easy availability of substrates.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Subhendu Pramanik, Sarat Chatterjee, Rumjhum Banerjee, Chinmay Chowdhury
Summary: This study presents a direct synthesis method for carbazoles containing aryl and aryl ketone groups. The reaction involves Pd(II)-catalyzed cascade reactions, which enables the fast assembly of carbazoles through four carbon-carbon bond formations. The absence of aldehyde substrates leads to the formation of C4-aryl-substituted carbazoles. The method is versatile for the synthesis of biscarbazole derivatives.