Novel facile synthesis of 2,2,4 substituted 1,2-dihydroquinolines via a modified Skraup reaction

A variety of 2,2,4 substituted 1,2-dihydroquinolines were synthesized from substituted anilines or aminoheterocycles and the corresponding ketones in good yield via the use of lanthanide catalysts and microwave technology. This method can be readily applied to the general synthesis of combinatorial libraries of dihydroquinolines.