66730-34-5Relevant academic research and scientific papers
Cascade C(sp3)-S Bond Cleavage and Imidoyl C-S Formation: Radical Cyclization of 2-Isocyanoaryl Thioethers toward 2-Substituted Benzothiazoles
Yang, Wen-Chao,Wei, Kai,Sun, Xue,Zhu, Jie,Wu, Lei
supporting information, p. 3144 - 3147 (2018/05/28)
A cascade radical cyclization of 2-isocyanoaryl thioethers with H-phosphorus oxides, organoboronic acids, or alkyl radical precursors has been efficiently developed, providing a novel and highly efficient methodology to structurally diverse C2-substituted benzothiazole derivatives with broad functional group tolerance and good yields. This cascade radical process achieves the first cycloaddition of an imidoyl radical from isocyanide to sulfur atom, rending C(sp2)-S bond formation.
TEMPO-Catalyzed Electrochemical C-H Thiolation: Synthesis of Benzothiazoles and Thiazolopyridines from Thioamides
Qian, Xiang-Yang,Li, Shu-Qi,Song, Jinshuai,Xu, Hai-Chao
, p. 2730 - 2734 (2017/05/31)
Benzothiazoles and thiazolopyridines are widely prevalent in pharmaceuticals and organic materials. Herein, we report a metal- and reagent-free method for the uniform synthesis of benzothiazoles and thiazolopyridines through 2,2,6,6-tetramethylpiperidine-N-oxyl radical (TEMPO)-catalyzed electrolytic C-H thiolation. This dehydrogenative coupling process provides access to a host of benzothiazoles and thiazolopyridines from N-(hetero)arylthioamides. Mechanistic studies suggested that the thioamide substrate was oxidized with the electrochemically generated TEMPO+ through an inner-sphere electron transfer to afford a thioamidyl radical, which undergoes homolytic aromatic substitution to form the key C-S bond.
Palladium-catalyzed direct functionalization of benzoxazoles with alkenyl iodides
Gerelle, Maria,Dalencon, Anne J.,Willis, Michael C.
, p. 1954 - 1957 (2012/05/07)
A straightforward procedure for the palladium-catalyzed direct functionalization of benzoxazoles with alkenyl iodides is described. The reactions employ a Pd(II)-precatalyst and use 'on water' conditions to achieve the ready union of a range of di- and tr
Palladium catalyzed coupling of tosylhydrazones with aryl and heteroaryl halides in the absence of external ligands: Synthesis of substituted olefins
Ojha, Devi Prasan,Prabhu, Kandikere Ramaiah
, p. 11027 - 11033 (2013/02/22)
Palladium catalyzed cross-coupling reaction of hydrazones with aryl halides in the absence of external ligand is reported. The versatility of this coupling reaction is demonstrated in showcasing the selectivity of coupling reaction in the presence of hydr
Neighboring Group Participation in Lewis Acid-Promoted and Annulations. The Stereocontrolled Synthesis of Tricyclic Ethers
Molander, Gary A.,Cameron, Kimberly O.
, p. 5931 - 5943 (2007/10/02)
A variety of 1,4- and 1,5-keto aldehydes derived from cycloalkanes are coupled with the bis(trimethylsilyl) enol ether of methyl acetoacetate in the presence of either TMSOTf or TrSbCl6 to generate tricyclic ethers.The reactions proceed with excellent regiochemical control by a mechanism involving neighboring group participation.This mechanism involves initial formation of a bicyclic oxocarbenium ion intermediate from the keto aldehyde substrates.The geometries of selected bicyclic intermediates have been optimized using the AM1 method allowing successful prediction of the stereochemical outcomes in the cyclization in most cases.Epimerization of α-chiral keto aldehyde substrates does not appear to occur in these Lewis acid-promoted annulation reactions.
