223565-36-4Relevant academic research and scientific papers
Switchable Access to 3-Carboxylate-4-quinolones and 1-Vinyl-3-carboxylate-4-quinolones via Oxidative Cyclization of Isatins and Alkynes
Jiang, Shi-Fen,Xu, Cheng,Zhou, Zhi-Wen,Zhang, Qin,Wen, Xiao-Hui,Jia, Feng-Cheng,Wu, An-Xin
, p. 4231 - 4234 (2018/07/29)
An efficient transition-metal-free oxidative cyclization reaction using isatins and alkynes for the facile synthesis of structurally diverse 4-quinolones has been developed. Intriguingly, switchable access to substituted 3-carboxylate-4-quinolones and 1-vinyl-3-carboxylate-4-quinolones could be achieved by choosing a different base in the reaction. The obtained products could undergo further transformations, increasing the application potential of the method in organic synthesis.
Facile one-pot syntheses of amidines and enamines from oximes via Beckmann rearrangement using trifluoromethanesulfonic anhydride
Takuwa, Tomofumi,Minowa, Tomofumi,Onishi, Jim Yoshitaka,Mukaiyama, Teruaki
, p. 1717 - 1725 (2007/10/03)
Iminocarbocation intermediates were in situ-generated by treating various oximes with trifluoromethanesulfonic anhydride (Tf2O) in the presence of triethylamine in toluene and nucleophilic trapping with amines or sodium enolates under mild conditions afforded the corresponding amidines and enamines. Some of the thus-obtained enamines were converted to 2-substituted 4-oxo-3-quinolinecarboxylic acid derivatives by subsequent intramolecular Friedel-Crafts acylation.
Synthesis of fluorinated 2-phenyl-4-quinolones from pyrrole-2,3-diones
Rao, V. V. Ramana,Wentrup, Curt
, p. 1232 - 1235 (2007/10/03)
A series of substituted 2-phenyl-4-quinolones 8-11 have been synthesized in good yields via flash vacuum thermolysis (FVT) of 1-aryl-4-cyano-5-phenylpyrrole-2,3-diones 7a-e and 1-aryl-4-methoxycarbonyl-5-phenylpyrrole-2,3-diones 7f-j. The pyrrolediones 7
Model studies related to synthesis and 1,4-dipolar cycloaddition reactions of mesoionic heterocycles
Issac, Yvette Abd El-Sayed
, p. 503 - 509 (2007/10/03)
The reaction of 2-(substituted amino)pyridine with reactive malonic acid derivatives provided an extremely facile synthesis of the mesoionic compound 4-oxo-4H-pyrido[1,2-a]pyrimidin-1-ium-2-olates. N,N'-Disubstituted amidine reacted with diethyl malonate to afford 4-quinolone in a one-pot cyclization and rearrangement (type A/I) of 4-oxopyridiniumolate 6. The latter compound was isolated via a reaction of acyclic amidine with AME's. A cycloaddition reaction of the mesoionic pyrimidine 6 with maleic anhydride or N- phenylmaleimide yielded [2+4] cycloadducts. Triphenyl pyrrolopyridinetrione 12 was achieved via a ring transformation of the cycloadduct 4-benzyl-3,5- dioxo-1,2,6-triphenyl-2,6-diazabicyclo[2.2.2]octane-7,8-dicarboxylic anhydride 11d. In contrast, the cycloadduct 4-ethyl derivative 11c and substituted 3,5-dioxo-1,2,6-triphenyl-2,6-diazabicyclo[2.2.2]octane-7,8- dicarboxylic N-phenylimides did not give 12 under the same reaction conditions. The mechanistic pathway for the formation of 12 was studied. Dimethyl acetylenedicarboxylate reacted with 6b,c to furnish 2-oxo-1,2- dihydropyridine-4,5-dicarboxylates.
