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Elimination Reaction of α,ω-diols by Magnesium

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Chinese Chemical Letters 1998年第8期9卷 697-698页

作者： Ji Mao LIN Hui ZHANG Ai You HAO Qin Zheng YANG(Department of Chemistry, Shandong University, Jinan, 250100) Department of Chemistry Shandong University Jinan 250100 China

1,3-Propanediol, 1,4-butanediol or 1,5-pentanediol reacts with magnesium to form corresponding magnesium alkoxides, which elindnate water with the formation of cyclic ethers and, respectively, allyl alcohol, 3-buten-1... 详细信息

关键词： elimination diols magnesium

Selective Monoprotection of Symmetrical diols in a Flow Reactor

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International Journal of Organic Chemistry 2018年第2期8卷 264-271页

作者： Hisashi Masui Masaru Takizawa Yuki Sakai Yasuhiro Kajiwara Kiyofumi Wanibuchi Mitsuru Shoji Takashi Takahashi Department of Pharmaceutical Sciences Yokohama University of Pharmacy Yokohama Japan

Desymmetrization reactions provide a powerful approach for the construction of complex molecules. Various methods have been developed for the selective monoprotection of symmetrical diols;however, their application to large-scale operations is limited. In this study, the monotetrahydropyranylation of symmetrical diols in a flow reactor has been developed, whereby the length of the flow reactor tube and the amount of acid were optimized. A higher selectivity for the monoprotected derivative was observed when the reaction was performed in a flow reactor compared with that observed in a conventional batch experiment. The efficient flow method developed herein can be applied to large-scale synthesis by numbering up the flow reactor without affecting the selectivity and yield. Since monoprotection can be achieved without using a large excess of diol, our developed flow method is effective when expensive diol must be used.

关键词： Desymmetrization Selective Monoprotection Flow Synthesis diols Tetrahydropyranylation

Facile Preparation of 1,2-diols from Chalcones: An NMR Spectroscopy and X-Ray Crystallography Study

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International Journal of Organic Chemistry 2015年第3期5卷 137-146页

作者： Marco A. Obregón-Mendoza María Miriam Estévez-Carmona Carolina Escobedo-Martínez Manuel Soriano-García Raúl G. Enríquez Instituto de Química Universidad Nacional Autónoma de México Ciudad Universitaria México City México Departamento de Farmacia División de Ciencias Naturales y Exactas del Campus Guanajuato Universidad de Guanajuato México

Structures of 2-(naphthalen-2-ylmethyl)-2,3-dihydro-1H-indene-1,2-diol (C20H18O2), compound 1 and 1-(3,4-dimethoxyphenyl)-3-methoxy-3-(4-nitrophenyl)propane-1,2-diol chloroform (C18H21NO7·CHCl3) compound 2 were established by spectral and X-ray diffraction studies. Compound 1 crystallizes in the orthorhombic space group P212121 with unit cell parameters a = 5.2177 (6), b = 13.903 (2), c = 21.121 (2) A, Z = 4. Compound 2 crystallizes in the triclinic space group P-1 with unit cell parameters a = 9.238 (1), b = 9.879 (1), c = 12.636 (1) A, α = 102.004 (1), β = 92.356 (1), γ = 90.779 (1)o, Z = 2. These two new molecules arise from a facile preparation of 1,2-diols from chalcones and have been fully characterized. Based on the crystallographic information obtained for compound 1, the relative configuration for the chiral centers is 1S and 2S. In structure 1, both hydroxyl groups adopt an anti-conformation with a torsion angle O1-C1-C2-O2 value of 93.1 (2)o [in molecule 2, both hydroxyl groups adopt a trans-conformation with a torsion angle O1-C1-C2-O2 value of -171.0 (2)。]. In both structures, the molecules in the crystal are linked by intermolecular hydrogen bonds O-H···O and C-H···O interactions and adjacent molecules are interconnected by intermolecular weak C-H···π and C-H···Cl interactions which give additional support to molecular packing stability.

关键词： C20H18O2 C18H21NO7·CHCl3 diols Chal-cones

Hydrophobic CHA-ZIFs with a junctional trap between cha and d6r cages for adsorption of 2,3-butanediol in aqueous solution

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Chinese Journal of Chemical Engineering 2024年第9期73卷 90-100页

作者： Lifang Ge Meizhen Gao Xiaosheng Zhang Jiang Wang Qi Shi Jinxiang Dong College of Chemical Engineering and Technology Shanxi Key Laboratory of Chemical Product EngineeringTaiyuan University of TechnologyTaiyuan 030024China

The adsorption and separation of diols from dilute aqueous solution using hydrophobic materials is very challenging due to the strong diol-water hydrogen-bonding interactions. Herein, we screened hydrophobic zeolitic imidazolate frameworks(ZIFs) with chabazite(CHA) topology for separation of 2,3-butanediol(2,3-BDO) and 1,3-propanediol(1,3-PDO), which had junctional and hydrophobic traps matching the two end methyl groups of the 2,3-BDO molecule. Based on CHA-ZIFs with the same small-sized ligand 2-methylimidazole(mIm) and different large-sized ligand benzimidazole derivatives(RbIm),CHA-ZIFs with larger surface areas were obtained by the addition of excess small-sized ligand mIm in the synthesis process. We showed that all of the hydrophobic CHA-ZIFs preferentially adsorbed 2,3-BDO over 1,3-PDO by static batch adsorption and dynamic column adsorption experiments. But ZIF-301 and ZIF-300 with halogen groups exhibited better adsorptive separation performance for 2,3-BDO/1,3-PDO than ZIF-302 with methyl groups. For a typical ZIF-301, its adsorption capacity for 2,3-BDO was 116.4 mg·g^(-1)and selectivity for 2,3-BDO/1,3-PDO was 3.8 in dynamic column adsorption of the binary-component system(2,3-BDO/1,3-PDO: 50 g·L^(-1)/50 g·L^(-1)). Computational simulations revealed that 2,3-BDO preferentially adsorbed in a trap at the junction between the cha and d6r cages of CHA-ZIFs,meaning the strong host-guest interactions. Therefore, the hydrophobic CHA-ZIFs with a junctional trap were promising candidate materials for adsorbing 2,3-BDO, which also provided a new perspective for separating diols in dilute aqueous solutions.

关键词： Adsorption Separation Aqueous solution Zeolitic imidazolate frameworks Junctional and hydrophobic trap diols

On the Absolute Configuration of Schweinfurthinol

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Chinese Journal of Chemistry 2011年第12期29卷 2759-2762页

作者：崔杉伍贻康高坡 School of Chemistry and Materials Heilongjiang University Harbin Heilongjiang 150080 China State Key Laboratory of Bioorganic and Natural Products Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

Through the chiral-pool based synthesis of both enantiomers of schweinfurthinol, it has been proven that this natural product isolated from the seeds of Canarium schweinfurthii possesses an （S） configuration. The op... 详细信息

关键词： natural products chiral building blocks diols phenols carbanions

One-pot-synthesis of novel cinchonine-based phosphites

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Chinese Chemical Letters 2009年第7期20卷 797-799页

作者： Qiao Feng Wang Xue Ying Liu Xiang Yang Qin Xiao Ye Li Sheng Yong Zhang Department of Chemistry Fourth Military Medical University Xi'an 710032 China

Cinchonine was employed as backbone for the synthesis of novel phosphite compounds with diol substituents. These monophosphinites were provided in one pot with the yields ranged from 63% to 75%. Their structures were confirmed by NMR spectroscopy and HRMS. C 2009 Sheng Yong Zhang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Cinchona alkaloids diols Chiral phosphite Asymmetric reaction Ligand

Investigation of Synthesis of Functionally Substituted Endiines and Their Chemical and Microbiological Conversion

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International Journal of Organic Chemistry 2013年第3期3卷 8-14页

作者： M. G. Veliyev M. A. Salmanov M. I. Shatirova S. R. Aliyeva L. N. Bunyatova Institute of Microbiology of Azerbaijan National Academy of Sciences Baku Azerbaijan Institute of Polymer Materials of Azerbaijan National Academy of Sciences Sumgayit Azerbaijan

The methods of preparation of endiine and endiallene diols by interaction of cis-1,4-dibrombutene and cis-1,4-dichlor-rbutene with monosubstituted acetylene alcohols in presence of the catalytic systems consisting of one-iodide copper, triethylamine and K2СО3 in a medium of dimethylformamide have been developed. It has been shown that unlike 1,4-dibrombutene, the nucleophilic substitution reaction with 1,4-dichlorbutene proceeds by acetylene-allene isomerization with formation of endiallene diols. It has been established that the endiine diols can be used in thin organic synthesis (in the reactions of oxidation, splitting, dehydration, epoxidation, hydrolysis, 1,2-cycloaddition and hypochlorination) with the aim of preparation of practically useful substances. It has been revealed during hydrolysis of epoxide compounds by the chemical and microbiological methods that in the course of microbiological hydrolysis (Aspеrgillus niger), the optically active trans-structured diols are formed.

关键词： Substitution Reaction Endiine diols Chemical Methods Oxidation of diols Hydrolysis of Epoxydiine Microbiological Hydrolysis Micromycetes

Aqueous-Phase, Palladium-Catalyzed Suzuki Reactions under Mild Conditions

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Green and Sustainable Chemistry 2013年第4期3卷 1-5页

作者： Yueqin Cai Gonghua Song Zhongyuan Wu Jiawei Zhang School of Chemistry and Molecular Engineering East China University of Science and Technology Shanghai China Shanghai Key Laboratory of Chemical Biology Institute of Pesticides & Pharmaceuticals East China University of Science and Technology Shanghai China

Water-soluble ionic liquid-supported diols have been used as phosphine-free ligands in Suzuki couplings of aryl idides/bromides/chlorides under mild conditions in aqueous solvent. It was found that 2,2-bis((1-hexylimidazolium)-mehyl) propane-1,3-diol hexafluorophosphate (4) in combination with palladium (II) salts gave the most significant catalyst. Suzuki couplings of aryl iodides/bromides occurred efficiently at room temperature in water/acetonitrile. Notably, the reactions of hydrophilic aryl bromides gave high yields in neat water. The catalyst PdCl2-4 was recycled five times in Suzuki couplings in water before catalyst activity began to significantly drop. The average yield of five cycles was >95% per cycle.

关键词： Suzuki Reaction Ionic Liquid-Supported diols Phosphine-Free Ligands

Synthesis and estrogen receptor binding selectivity of 2-Phenylbenzofuran Derivatives

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Synthesis and estrogen receptor binding selectivity of 2-Phe...