Lei, Jie published the artcileA concise and unexpected one-pot methodology for the synthesis of pyrazinone-fused pyridones, COA of Formula: C8H7NO4, the publication is Organic Chemistry Frontiers (2020), 7(18), 2657-2663, database is CAplus.
A facile one-pot cascade reaction for the synthesis of pyrazinone-fused pyridones I [R1 = H, 5-Cl, 5-Br; R2 = 4-BrC6H4, 4-O2NC6H4, 4-NCC6H4, etc.; R3 = (CH2)3CH3, cyclohexyl, 4-MeOC6H4, 2,6-di-MeC6H3, 2-Cl-6-MeC6H3, (CH2)2C6H5]/pyridones II [R4 = prop-2-ynyl, 3,5-di-MeC6H3, Bn, 1-(2-thienylmethyl); R5 = 2,6-di-MeC6H3, Bn, (CH2)2C6H5; R6 = H, 5-Br; R7 = 4-O2NC6H4, 4-NCC6H4] was developed without a metal catalyst. Hydroamination of the Ugi propargyl adducts arising from aromatic isocyanides would be promoted by the intramol. protonation of the alkyne with the amide NH to form an unstable oxazolopyridinium. The cascade reaction was applied to alkyl isocyanide to synthesize pyrazinone-fused pyridones under strongly acidic conditions. This novel cascade reaction proceeded through an Ugi/Michael/Retro-Michael reaction, aromatization and 5-exo-dig cyclization cascade sequence. The reaction features a simple operation procedure, one purification step and good yields, which could be applicable to a broad scope of Ugi starting materials. This was the first report on the intramol. hydroamination occurring between an amide and an alkyne under conditions with an organic base.
Organic Chemistry Frontiers published new progress about 104-03-0. 104-03-0 belongs to catalysis-chemistry, auxiliary class Nitro Compound,Carboxylic acid,Benzene, name is 4-Nitrophenylacetic acid, and the molecular formula is C8H7NO4, COA of Formula: C8H7NO4.
Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia