51860-45-8Relevant articles and documents
Acid-catalysed intramolecular addition of β-ketoesters to 1,3-dienes
Vayer, Marie,Fang, Weizhen,Guillot, Régis,Bezzenine-Lafollée, Sophie,Bour, Christophe,Gandon, Vincent
, p. 584 - 588 (2017)
1,3-Dienyl β-keto esters are cyclised into bicyclolactones using the Bi(OTf)3/TfOH catalytic system. This reaction represents a rare case of simultaneous C-C and C-O bond formation at positions 1 and 3 of a 1,3-diene. Application to the synthesis of ramulosin is presented.
Palladium-Catalyzed Tandem Hydrocarbonylative Lactamization and Cycloaddition Reaction for the Construction of Bridged Polycyclic Lactams
Xu, Pengcheng,Qian, Bo,Hu, Bin,Huang, Hanmin
supporting information, p. 147 - 151 (2022/01/04)
The intramolecular hydroaminocarbonylation of alkenes is a compelling tool to rapidly access lactam, a privileged motif ubiquitous in natural products, pharmaceuticals, and agrochemicals. However, selective carbonylation to bridged polycyclic lactams with a lactam nitrogen at a bridgehead position is less explored. We herein report a modular palladium-catalyzed approach to perform a tandem hydrocarbonylative lactamization/Diels-Alder cycloaddition reaction with 2-vinyl aryl aldimines, alkenes, and CO, which offers convenient access to furnish the bridged polycyclic lactams in high yields with high selectivities.
HEPTADECATRIENE SIDE CHAIN HYDROQUINONE DERIVATIVE SYNTHESIS METHOD
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Paragraph 0027; 0029; 0044-0046, (2021/05/05)
PROBLEM TO BE SOLVED: To provide a heptadecatriene side chain hydroquinone derivative synthesis method in which heptadecatriene side chain hydroquinone derivative being more stable than catechol and the final product being non-oily but solid can be synthe
Phosphonium-based ionic liquids: Economic and efficient catalysts for the solvent-free cycloaddition of CO2 to epoxidized soybean vegetable oil to obtain potential bio-based polymers precursors
Centeno-Pedrazo, A.,Freixa, Z.,Garcia-Suarez, E. J.,Perez-Arce, J.,Prieto-Fernandez, S.
, (2021/10/01)
A series of phosphonium-based ionic liquids have been prepared in one step in a simple way from inexpensive feedstocks. The prepared ionic liquids have been successfully tested as catalysts in the solvent-free cycloaddition reaction of CO2 to an epoxidized soybean oil to obtain carbonated soybean oil that can be potentially employed as bio-monomer in the synthesis for bio-based polymers. The catalytic performance of these ionic liquids was compared to the widely used and benchmark catalyst in CO2 cycloaddition to epoxides reaction, namely tetrabutylammonium bromide at different reaction conditions. The influence of some reaction parameters such as temperature, CO2 pressure, reaction time and catalyst amount was studied. It has been found that the solubility of the prepared ionic liquids in the reaction media (epoxidized soybean oil) is a key factor that limits the catalytic performance of some of the synthesized ionic liquids. All prepared ionic liquids have shown higher thermal stability that the benchmark catalyst and three of them have shown superior catalytic performance. The best results in terms of conversion and selectivity have been obtained with dodecyltriphenylphosphonium bromide (5) achieving almost full conversion (99.8%) and excellent selectivity (84.0%) after 5 h reaction at 160 oC and 40 bar of CO2. Outstanding results compared to those reported in the literature with similar catalysts in the solvent-free CO2 cycloaddtion to an epoxidized soybean oil to obtain the corresponding carbonated oil have been achieved. Considering the facile synthesis of catalyst 5, the large availability and non-expensive of the feedstocks and its catalytic performance it can be considered a valuable and green alternative for CO2 fixation to epoxidized vegetable oil.
