Synthesis of fatty ketoesters by tandem epoxidation–rearrangement with heterogeneous catalysis
作者:Vicente Dorado、Lena Gil、José A. Mayoral、Clara I. Herrerías、José M. Fraile
DOI:10.1039/c9cy01899a
日期:——
Fatty ketoesters are obtained from unsaturated fatty esters in a tandem two-step process with a combination of two heterogeneous catalysts, without intermediate purification and with maximum productivity of the catalysts through recycling and reuse.
Fatty acid based biocarbonates: Al-mediated stereoselective preparation of mono-, di- and tricarbonates under mild and solvent-less conditions
作者:L. Peña Carrodeguas、À. Cristòfol、J. M. Fraile、J. A. Mayoral、V. Dorado、C. I. Herrerías、A. W. Kleij
DOI:10.1039/c7gc01206c
日期:——
A catalytic method for the preparation of a series of fatty acid derived biocarbonates has been developed using a binary Al-complex/PPNCl catalyst. This catalyst system allows conversion of fatty acid derived epoxides under comparatively mild reaction conditions (70–85 °C, 10 bar) while maintaining high levels of diastereospecificity with cis/trans ratios of up to 97:3 in the products. The comparative
Influence of alkenyl structures on the epoxidation of unsaturated fatty acid methyl esters and vegetable oils
作者:Yao-Bing Huang、Meng-Yue Yao、Ping-Ping Xin、Meng-Chao Zhou、Tao Yang、Hui Pan
DOI:10.1039/c5ra11035a
日期:——
Epoxidation of vegetable oils or fatty acidmethylesters (FAMEs) produce important monomers which are widely used as plasticizers or stabilizers in the polymer industry. However, little attention has been focused on the influence of the alkenyl structure of the fatty acid on the efficiency and selectivity of their epoxidation. In this work, the influence of the alkenyl structure (the number of double bonds)
植物油或脂肪酸甲酯(FAME)的环氧化产生重要的单体,这些单体在聚合物工业中被广泛用作增塑剂或稳定剂。但是,很少有注意力集中在脂肪酸的烯基结构对其环氧化效率和选择性的影响上。在这项工作中,已研究了FAME的烯基结构(双键数)对环氧化反应的影响。使用弱酸(甲酸)和强酸(硫酸/乙酸)系统对具有1至3个双键的三个模型FAME进行环氧化。发现具有更多双键的FAME对环氧化反应具有更高的反应性。此外,脂肪酸链上双键的供电子作用趋于稳定与弱酸体系相邻的环氧化物。此外,具有更多双键的FAME容易与强酸体系发生副反应(H2 SO 4)。用相同的两种酸催化剂体系对具有不同脂肪酸组成的两种植物油进行环氧化。结果与FAME的结果一致。目前的发现可以为具有不同烯基结构组成的不同植物油的环氧化提供有用的指导。
Epoxidation of Polyunsaturated Fatty Acid Double Bonds by Dioxirane Reagent: Regioselectivity and Lipid Supramolecular Organization
作者:Stanislav A. Grabovskiy、Natalia N. Kabal'nova、Chryssostomos Chatgilialoglu、Carla Ferreri
DOI:10.1002/hlca.200690209
日期:2006.10
reaction outcome, and the epoxidation showed interesting regioselective features. The CC bonds closest to the aqueous-micelle interface is the most favored for the interaction with dimethyldioxirane. The preferential epoxidation of linoleic acid (= (9Z,12Z)-octadeca-9,12-dienoic acid) to the 9,10-monoepoxy derivative was achieved, with a high yield and 65% regioselectivity. In case of arachidonic acid
Calcium-Based Catalytic System for the Synthesis of Bio-Derived Cyclic Carbonates under Mild Conditions
作者:Lars Longwitz、Johannes Steinbauer、Anke Spannenberg、Thomas Werner
DOI:10.1021/acscatal.7b03367
日期:2018.1.5
Recently, bio-derived cycliccarbonates have gained significant importance: e.g., as building blocks in non-isocyanate polyurethanes (NIPUs). Herein we report the development of a calcium-based catalyst system for the synthesis of challenging internal and trisubstituted cycliccarbonates from bio-derived epoxides and CO2 under mild reaction conditions. Several crown ethers were tested as ligands in
近来,生物来源的环状碳酸酯已变得非常重要:例如,作为非异氰酸酯聚氨酯(NIPU)中的结构单元。本文中,我们报告了在温和的反应条件下,由生物衍生的环氧化物和CO 2合成具有挑战性的内部和三取代的环状碳酸酯的钙基催化剂系统的开发。测试了几种冠醚作为配体与各种助催化剂的配体,以活化CO 2。活性最高的系统除碘化钙外,还由二环己基官能化的18冠-6醚和三苯基膦组成。用1检测到冠状醚在原位络合Ca 2+。1 H NMR光谱。有趣的是,加入三苯基膦作为助催化剂可显着提高活性,这与有机超碱(如DBU和TBD)的活性相似或什至更高。该催化体系用于将16种不同的生物衍生环氧化物(包括脂肪酸酯,油和萜烯)与CO 2进行转化,并能够在温和条件下促进反应。各种内部环氧化物仅在45℃,0.5 MPa CO 2压力,5摩尔%的催化剂负载量和24小时的反应时间下转化,分离出的收率最高为相应碳酸盐的98%。尽管需要更苛刻