17817-32-2Relevant articles and documents
Chemistry of Thienopyridines. XXXV. Synthesis, Tautomerism, and Reactions of Quinoline and Thienopyridine Systems Which Bear a 1-Carboethoxy-1-cyanomethyl Substituent in the Pyridine Ring, Part 2
Klemm, L.H.,Lu, Jennifer J.,Greene, Diana S.,Boisvert, William
, p. 1467 - 1472 (2007/10/02)
A comparison is made amongst the isosteric systems quinoline, thienopyridine, and thieno-pyridine which bear the 1-carboethoxy-1-cyanomethyl substituent (R) alpha or gamma to the heterocyclic nitrogen atom.Treatment of thienopyridine 4-oxide with ethyl cyanoacetate and acetic anhydride at room temperature (Hamana reaction) gives the alpha R-derivative 6 (27percent), formulated as an intramolecular H-bonded structure.Neither 6 nor its quinoline alpha analog reacts with refluxing acetic anhydride, while the quinoline gamma isomer 8, existing as NH and CH tautomers, yields an N-acetyl derivative 10 (70percent) under similar conditions.For each of 6 and 8 one can isolate two crystalline forms which differ considerably in color.Compound 10 and its gamma analog in the thienopyridine series (previously obtained directly from a Hamana reaction) serve as acetylating agents for aniline, 1-aminobutane, morpholine, and cholesterol.Correlations and contrasts in the three systems are presented.
