Three-component domino reactions in the synthesis of polyfluoroalkyl-containing tetrahydropyrido[2,1-b]quinazolines
摘要
The three-component reaction of polyfluoroalkyl-3-oxo esters with α,β-unsaturated aldehydes and 2-(aminomethyl)aniline afforded 8-(polyfluoro-1-hydroxyalkyl)-6,7,8,11-tetrahydro-9H-pyrido[2,1-b]quinazolin-9-ones upon heating; under mild conditions, this reaction gave bicyclic dihydroquinazoline intermediates, CF3 derivatives of which exist in the form of bases and their C2F5 analogues exist in the form of salts. The diastereomeric and tautomeric structures of the new heterocycles were studied by 1H, 19F, and 13C NMR spectroscopy, IR spectroscopy, and X-ray diffraction. A domino mechanism for their formation was proposed.