3488-55-9Relevant academic research and scientific papers
Electrochemical synthesis of 1,2,4-oxadiazoles from amidoximes through dehydrogenative cyclization
Hu, Aixi,Jiang, chan,Li, mingfang,Xu, Leitao,Ye, Jiao,Yi, Yangjie
supporting information, p. 10611 - 10616 (2021/12/27)
A convenient and efficient method for the generation of the iminoxy radical through anodic oxidation was developed for the synthesis of 3,5-disubstituted 1,2,4-oxadiazoles fromN-benzyl amidoximes. The transformation proceeds through 1.5-Hydrogen Atom Transfer (1,5-HAT) and intramolecular cyclization. The process features simple operation, mild conditions, broad substrate scope and high functional group compatibility, and provides a facile and practical way for the preparation of 1,2,4-oxadiazoles.
Copper-Catalyzed Three-Component Cascade Reaction of Benzaldehyde with Benzylamine and Hydroxylamine or Aniline: Synthesis of 1,2,4-Oxadiazoles and Quinazolines
Wang, Chao,Rui, Xiyan,Si, Dongjuan,Dai, Rupeng,Zhu, Yueyue,Wen, Hongmei,Li, Wei,Liu, Jian
supporting information, p. 2825 - 2833 (2021/04/26)
The analogous three-component synthesis strategy for substituted 1,2,4-oxadiazole and quinazoline derivatives from readily available benzaldehyde, benzylamine and hydroxylamine or aniline has been developed. Both the cascade reaction sequences involves nucleophilic addition of C?N bond, introduction a halogen donor, nucleophilic substitution and Cu(II)-catalyzed aerobic oxidation. This synthesis methodology demonstrated good yields, broad substrate scope and oxygen as a green oxidant. Thus, this synthesis protocol provides strategies for the construction of substituted 1,2,4-oxadiazole and quinazolines from readily and simple starting materials. (Figure presented.).
Easy Access to 1-Amino and 1-Carbon Substituted Isoquinolines via Cobalt-Catalyzed C - H/N - O Bond Activation
Muralirajan, Krishnamoorthy,Kuppusamy, Ramajayam,Prakash, Sekar,Cheng, Chien-Hong
supporting information, p. 774 - 783 (2016/03/09)
A green atom-economical method for the synthesis of highly functionalized 1-amino and 1-carbon substituted isoquinolines from the reaction of N′-hydroxybenzimidamides and aryl ketoximes, respectively, with alkynes via pentamethylcyclopentadienylcobalt(III)-catalyzed C - H/N - O bond activation is described. The external oxidant-free annulation reaction uses the =NOH moiety in N′-hydroxybenzimidamides or N-aromatic ketone oximes as the directing group and internal oxidant. This first row transition metal-catalyzed annulation serves as an efficient alternative for the synthesis of isoquinolines, as water is the only by-product and expensive noble metals such as rhodium(III), iridium(III), palladium(II), and ruthenium(II) are not required. The reaction proceeds via C - H activation, alkyne insertion, reductive elimination, and N - O activation.
Synthesis of 1,2,4-Oxadiazoles via DDQ-Mediated Oxidative Cyclization of Amidoximes
Parker, Patrick D.,Pierce, Joshua G.
, p. 1902 - 1909 (2016/06/15)
An oxidative cyclization of amidoximes to form 1,2,4-oxadiazoles, mediated by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), is described. A range of alkyl, aryl, and heteroaryl substrates are tolerated under these conditions. This reaction serves as an alternate approach for the synthesis of functionally diverse oxadiazoles via a rapid and straightforward synthetic procedure.
Copper-catalyzed redox-neutral C-H amination with amidoximes
Chen, Hui,Chiba, Shunsuke
supporting information, p. 42 - 46 (2014/01/06)
CuI-catalyzed reactions of N-alkylamidoximes afforded dihydroimidazoles via sp3 C-H amination. On the other hand, the reactions of N-benzoylamidoximes resulted in sp2 C-H amination to form quinazolinones. The reaction mechanisms could be characterized as a redox-neutral radical pathway including a Cu(i)-Cu(ii) redox catalytic cycle. The Royal Society of Chemistry.
Orthogonal aerobic conversion of N-benzyl amidoximes to 1,2,4-oxadiazoles or quinazolinones
Zhang, Feng-Lian,Wang, Yi-Feng,Chiba, Shunsuke
supporting information, p. 6003 - 6007 (2013/09/12)
Concise synthesis of 1,2,4-oxadiazoles was achieved by heating N-benzyl amidoximes with K3PO4 in DMF at 60°C under an O 2 atmosphere via benzylic C-H oxygenation. On the other hand, aerobic treatment of N-benzyl amidoximes
