1797-74-6Relevant academic research and scientific papers
Photoinduced Diverse Reactivity of Diazo Compounds with Nitrosoarenes
Roy, Sourav,Kumar, Gourav,Chatterjee, Indranil
supporting information, p. 6709 - 6713 (2021/09/08)
A diverse reactivity of diazo compounds with nitrosoarene in an oxygen-transfer process and a formal [2 + 2] cycloaddition is reported. Nitosoarene has been exploited as a mild oxygen source to oxidize an in situ generated carbene intermediate under visible-light irradiation. UV-light-mediated in situ generated ketenes react with nitosoarenes to deliver oxazetidine derivatives. These operationally simple processes exemplify a transition-metal-free and catalyst-free protocol to give structurally diverse α-ketoesters or oxazetidines.
Preparation of Organic Nitrates from Aryldiazoacetates and Fe(NO3)3·9H2O
Thurow, Samuel,Fernandes, Alessandra A. G.,Quevedo-Acosta, Yovanny,De Oliveira, Matheus F.,De Oliveira, Marcelo G.,Jurberg, Igor D.
supporting information, p. 6909 - 6913 (2019/09/12)
A thermal protocol is reported for the formal insertion of nitric acid into aryldiazoacetates using Fe(NO3)3·9H2O. This strategy is mild and high yielding and allows the preparation of a large variety of members of an unprecedented family of organic nitrates. The nitrate group can be also readily transformed into other functional groups and heterocyclic moieties and can possibly allow new biological explorations of untapped potential associated with their NO-releasing ability.
LED lighting as a simple, inexpensive, and sustainable alternative for Wolff rearrangements
Bernardim, Barbara,Hardman-Baldwin, Andrea M.,Burtoloso, Antonio C. B.
, p. 13311 - 13314 (2015/02/19)
The Wolff rearrangement is one of the best methods for chain homologation. However, it still suffers from many drawbacks with respect to its practical execution in the laboratory. We wish to demonstrate the use of commercial LED lamps as a sustainable alternative for the classic experimental protocols typically used for Wolff rearrangements. This journal is
SO3H and NH2+ functional carbon-based solid acid catalyzed transesterification and biodiesel production
Cai, Liangzhen,Meng, Decai,Zhan, Shaoqi,Yang, Xiaoxia,Liu, Taoping,Pu, Huiming,Tao, Xiaochun
, p. 72146 - 72149 (2015/09/08)
A SO3H and NH2+ functional carbon-based solid acid was used as a highly active heterogeneous catalyst for the transesterification of various carboxylic methyl esters with alcohols under mild conditions. It also showed high catalytic performance for transesterification of triolein with methanol or isopropanol. Furthermore, it was able to catalyze simultaneous esterification and transesterification of rice oil and butter respectively, the yields of biodiesel obtained were up to 94%, and the catalyst could be easily recovered and reused more than ten times without loss of activity, which indicated the carbon-based solid acid was a potential catalyst for the biodiesel industry.
The carbon material functionalized with NH2+ and SO3H groups catalyzed esterification with high activity and selectivity
Zhan, Shaoqi,Tao, Xiaochun,Cai, Liangzhen,Liu, Xiaohui,Liu, Taoping
supporting information, p. 4649 - 4653 (2015/02/19)
A novel carbon-based solid acid was conveniently prepared by heating a mixture of d-glucose, p-toluenesulfonic acid and diphenylammonium tosylate. Its structure was measured by XRD, FT-IR, XPS, 13C MAS NMR and EA to illustrate that the carbon material has been functionalized with NH2+ and SO3H groups and has a strong "hydrophobic effect". It can be used to catalyze the esterification reaction of carboxylic acids with equimolar amounts of sterically demanding and acid-sensitive alcohols with high reactivity (yield up to 90%) and selectivity (up to 95%) in heptane at 80 °C. It could be easily recovered and reused more than ten times without loss of activity.
Copper(II)-acid catalyzed cyclopropanation of 1,3-dienamides by electrophilic activation of α-aryl diazoesters
Tayama, Eiji,Horikawa, Kouki,Iwamoto, Hajime,Hasegawa, Eietsu
supporting information, p. 3041 - 3044 (2014/05/20)
Copper(II)-acid catalyzed cyclopropanation of electron-rich alkenes, such as 1,3-dienamides, with α-aryl diazoesters are described. The reaction could be performed without rare metal catalysts, excess substrate, or the need for the slow addition of the diazoesters.
Palladium-catalyzed divergent reactions of α-diazocarbonyl compounds with allylic esters: Construction of quaternary carbon centers
Chen, Zi-Sheng,Duan, Xin-Hua,Zhou, Ping-Xin,Ali, Shaukat,Luo, Jian-Yi,Liang, Yong-Min
supporting information; experimental part, p. 1370 - 1374 (2012/03/27)
Take two: α-Diazocarbonyl compounds display a diverse pattern of reactivity upon palladium-catalyzed reaction with esters. Esters bearing an alkynyl group on the carbonyl carbon atom lead to two different C-C bonds at the same carbon atom in a single operation through decarboxylation and migratory insertion, whereas aromatic and benzylic acid derivatives afford aromatic and benzylic esters bearing an O-substituted quaternary carbon center. Copyright
Use of diethoxymethane as a solvent for phase-transfer esterification of carboxylic acids
Coleman, M. Todd
scheme or table, p. 1911 - 1913 (2012/06/04)
The esterification of carboxylic acids with selected primary alkyl halides in diethoxymethane (DEM) utilizing solid-liquid phase-transfer catalysis has been studied. The use of DEM as the solvent simplifies the process in that a single solvent can be used for both reaction and workup.
Protic acid immobilized on solid support as an extremely efficient recyclable catalyst system for a direct and atom economical esterification of carboxylic acids with alcohols
Chakraborti, Asit K.,Singh, Bavneet,Chankeshwara, Sunay V.,Patel, Alpesh R.
supporting information; experimental part, p. 5967 - 5974 (2009/12/24)
(Chemical Equation Presented) A convenient and clean procedure of esterification is reported by direct condensation of equimolar amounts of carboxylic acids with alcohols catalyzed by an easy to prepare catalyst system of perchloric acid immobilized on silica gel (HClO4-SiO2). The direct condensation of aryl, heteroaryl, styryl, aryl alkyl, alkyl, cycloalkyl, and long-chain aliphatic carboxylic acids with primary/secondary alkyl/cycloalkyl, allyl, propargyl, and long-chain aliphatic alcohols has been achieved to afford the corresponding esters in excellent yields. Chiral alcohol and N-t-Boc protected chiral amino acid also resulted in ester formation with the representative carboxylic acid or alcohol without competitive N-t-Boc deprotection and detrimental effect on the optical purity of the product demonstrating the mildness and chemoselectivity of the procedure. The esters of long-chain (>C10) acids and alcohols are obtained in high yields. The catalyst is recovered and recycled without significant loss of activity. The industrial application of the esterification process is demonstrated by the synthesis of prodrugs of ibuprofen and a few commercial flavoring agents. Other protic acids such as H2SO4, HBr, TfOH, HBF4, and TFA that were adsorbed on silica gel were less effective compared to HClO4-SiO2 following the order HClO4-SiO 2 ? H2SO4-SiO2 > HBr-SiO 2 > TfOH-SiO2 ? HBF4-SiO2 ≈ TFA-SiO2. When HClO4 was immobilized on other solid supports the catalytic efficiency followed the order HClO4-SiO 2 > HClO4-K10 > HClO4-Al 2O3 (neutral) > HClO4-Al2O 3 (acidic) > HClO4-Al2O3 (basic).
Studies on the structure-activity relationship of bicifadine analogs as monoamine transporter inhibitors
Zhang, Mingzhu,Jovic, Florence,Vickers, Troy,Dyck, Brian,Tamiya, Junko,Grey, Jonathan,Tran, Joe A.,Fleck, Beth A.,Pick, Rebecca,Foster, Alan C.,Chen, Chen
scheme or table, p. 3682 - 3686 (2009/04/06)
Compounds with various activities and selectivities were discovered through structure-activity relationship studies of bicifadine analogs as monoamine transporter inhibitors. The norepinephrine-selective 2-thienyl compound S-6j was efficacious in a rodent
