116655-45-9Relevant academic research and scientific papers
TAUTOMERISM OF DERIVATIVES OF AZINES. 16. TAUTOMERISM OF ACYLMETHYLPYRAZINES AND -QUINOXALINES
Mainagashev, I. Ya.,Lapachev, V. V.,Fedotov, M. A.,Mamaev, V. P.
, p. 1339 - 1342 (2007/10/02)
The tautomeric equilibria of acylmethylpyrazines and -quinoxalines in chloroform were studied by 1H, 14N, and 17O NMR spectroscopy.It was shown that keto-enol tautomerism is realized in the acylmethylpyrazine series.Annelation leads to the development of an ylidene tautomer in the acylmethylquinoxaline series.A marked dependence of the position of the intrachelate equilibrium on the character of the solvent was observed.
Alkynyl- and Dialkynyl-quinoxalines. Synthesis of Condensed Quinoxalines
Ames, Donald E.,Brohi, M. Ismail
, p. 1384 - 1389 (2007/10/02)
Condensation of 2-chloro- and 2,3-dichloroquinoxalines with alk-1-ynes in the presence of bis(triphenylphosphine)palladium(II) dichloride and copper(I) iodide gives mono- and di-alkynylquinoxalines.Addition of amines to these products gives stable enamines; hydration gives 2'-oxoalkyl compounds which exist predominantly in the intramolecularly hydrogen-bonded enol form.Condensation of the alkynylquinoxalines with diethyl sodiomalonate, and related compounds, yields pyridoquinoxalin-4-one derivatives. 2-Alkynyl-3-chloroquinoxalines are intermediates for convenient syntheses of pyrroloquinoxalines.
