3532-20-5Relevant academic research and scientific papers
Iridium(III)-Catalyzed Selective and Mild C-H Amidation of Cyclic N-Sulfonyl Ketimines with Organic Azides
Maraswami, Manikantha,Chen, Gang,Loh, Teck-Peng
supporting information, p. 416 - 421 (2017/11/13)
A general protocol for iridium catalyzed direct C?H amidation of cyclic N-sulfonyl ketimines using sulfonyl, acyl and aryl azides as nitrogen source is reported herein. The reaction takes place at room temperature with acyl and aryl azides, while an elevated temperature needed with sulfonyl azides to furnish aminated sultams in excellent yields with complete chemo and regioselectivity, thus providing a robust and environmentally benign process to the synthesis of aminosultams. (Figure presented.).
Synthesis of Acyl Azides from 1,3-Diketones via Oxidative Cleavage of Two C-C Bonds
Yu, Tian-Yang,Zheng, Zhao-Jing,Dang, Tong-Tong,Zhang, Fang-Xia,Wei, Hao
, p. 10589 - 10594 (2018/09/06)
A metal-free PhI(OAc)2-mediated method for the synthesis of acyl azides through oxidative cleavage of 1,3-diketones is described. This method is shown to have a broad substrate scope, providing a useful tool for multiproduct synthesis in a single procedure. A possible reaction pathway is proposed based on mechanistic studies.
An investigation on practical synthesis of carboxylic acid derivatives using p-toluenesulfonyl chloride
Eskandari, Parvin,Kazemi, Foad
, p. 431 - 439 (2017/07/24)
Carboxylic acid derivatives are well recognized as important class of reagents frequently used in the preparation of a variety of fine or special chemicals such as amides, esters, peptides, drugs, and dyes. Although several methods were developed for the preparation of these compounds, many of them present difficulties, including low yield, high reaction temperature, harsh reaction conditions, tedious work-up, and incompatibility with scale-up. Methods: The synthesis of carboxylic anhydrides is developed through the reaction of carboxylic acids with TsCl in the presence of K2CO3 and acetonitrile as a solvent under ultrasound irradiation and conventional conditions. In addition, one-pot synthesis of acyl azides was carried out in the presence of produced carboxylic anhydrides and the addition of sodium azide under identical condition. Results: A series of carboxylic anhydrides and acyl azides were synthesized using TsCl under ultrasound irradiation and conventional stirring with simple procedure, mild reaction conditions, high yields, and scale-up ability without any restriction. In most cases, the reaction under ultrasound irradiation was better in both yields and the reaction times compared to the conventional method. Conclusion: A convenient method has been developed for the preparation of carboxylic anhydrides and acyl azides under ultrasound irradiation and conventional stirring. The present method is practical and a highly effective alternative for previous reports. The major advantages of this method are: (i) simplicity of the procedure (ii) high yields and high purity of product (iii) scale-up capacity without considerable limitation in conventional system. Under ultrasound irradiation short reaction times as compared to conventional method are observed; yields are comparable to or better than conventional method.
Metal-mediated reactions of aryl isocyanates with dimethoxycarbene to form isatin derivatives
Rigby, James H.,Brouet, Stephanie A.
supporting information, p. 2542 - 2545 (2013/06/05)
Hydantoin derivatives have been established as the observed product in the reaction of aryl isocyanates with dimethoxycarbene. A change in the reactivity profile of dimethoxycarbene with aryl isocyanates was observed upon the addition of a metal species.
Novel VEGFR-2 kinase inhibitors identified by the back-to-front approach
Sanphanya, Kingkan,Wattanapitayakul, Suvara K.,Phowichit, Suwadee,Fokin, Valery V.,Vajragupta, Opa
supporting information, p. 2962 - 2967 (2013/06/27)
We report a novel VEGFR-2 inhibitor, developed by the back-to-front approach. Docking experiments indicated that the 3-chloromethylphenylurea motif of the lead compound occupied the back pocket of VEGFR-2 kinase. An attempt was made to enhance the binding affinity of 1 by expanding the structure to access the front pocket using a triazole linker. A library of 1,4-(disubstituted)-1H-1, 2,3-triazoles were screened in silico, and one compound (VH02) was identified with an IC50 against VEGFR-2 of 0.56 μM. VH02 showed antiangiogenic effects, inhibiting tube formation in HUVEC cells (EA.hy926) at 0.3 μM, 13 times lower than its cytotoxic dose. These enzymatic and cellular activities suggest that VH02 has potential as a lead for further optimization.
Palladium-catalyzed aromatic azidocarbonylation
Miloserdov, Fedor M.,Grushin, Vladimir V.
supporting information; experimental part, p. 3668 - 3672 (2012/05/20)
Aryl iodides smoothly react with NaN3 and CO in the presence of a Pd/Xantphos catalyst to give aroyl azides (ArCON3) in 75-92 % yield. The reaction occurs under mild reaction conditions (1 atm, 20-50 °C) and exhibits high functional-group tolerance. (Xantphos=9,9-dimethyl-4,5- bis(diphenylphosphino)xanthene)
Direct synthesis of acyl azides from carboxylic acids using 2-azido-l,3-dimethylimidazolinium chloride
Kitamura, Mitsuru,Tashiro, Norifumi,Takamoto, Yusuke,Okauchi, Tatsuo
scheme or table, p. 731 - 733 (2011/01/08)
Acyl azides were directly synthesized from carboxylic acids by the treatment with 2-azido-l,3-dimethylimidazolinium chloride (ADMC, 1) and amine. This procedure resulted in acyl azides in good yields and was applied to the amidation of amino acid derivatives without racemization of the products.
Oxidative amidation and azidation of aldehydes by NHC catalysis
De Sarkar, Suman,Studer, Armido
supporting information; experimental part, p. 1992 - 1995 (2010/07/10)
Figure presented N-Heterocyclic carbene catalyzed oxidative amidations of various aldehydes to the corresponding hexafluoroisopropylesters by using the readily available organic oxidant A are described. The hexafluoroisopropylesters prepared in situ are shown to be highly useful active esters for amide bond formation. In addition, oxidative azidation of aldehydes is presented. These mild organocatalytic processes do not use any transition metal.
Thiol on silica as a 'catch and release' support for isocyanates to afford ureas
Bolshan, Yuri,Tomaszewski, Miroslaw J.,Santhakumar, Vijayaratnam
, p. 4925 - 4927 (2008/02/08)
Silica-bound thiocarbamates were prepared by Curtius rearrangement of carboxylic acids in the presence of thiol on silica gel. The solid supported thiocarbamates were found to be stable isocyanate equivalents, which upon treatment with amines efficiently afforded di- and tri-substituted ureas. The urea products released from the catch and release support were, in the majority of cases, greater than 95% pure and required no further work up.
Rapid construction of isatin derivatives via addition of bis(alkylthio)carbenes to aryl isocyanates
Rigby, James H.,Danca, M. Diana
, p. 6891 - 6894 (2007/10/03)
Thermally induced cyclization between bis(alkylthio)carbenes, derived from the corresponding oxadiazolines, and substituted aryl isocyanates provides access to a variety of isatin derivatives with good efficiency.
