Utility of the Pfitzinger Reaction in the Synthesis of Novel Quinoline Derivatives and Related Heterocycles

Abstract

in Wiley Online Library (wileyonlinelibrary.com). 1 3 4 9 12 10a-d2-(2-Amino-3,5-dinitrophenyl)-2-oxoacetic acid (2) was obtained from hydrolysis of 5,7-dinitroisatin (1) in alkaline media. A novel quinoxaline derivative (3) was synthesized from the reaction of the same compound (1) with o-phenylenediamine. Reacting 2 with ethyl 3-oxo-3-phenylpropanoate yields 6,8-dinitro-2-phenylquinoline-3,4-dicarboxylic acid (4). Then, 4 was converted into new quinoline-diacylchloride, quinoline-ester, quinolinedicarboxamide, pyridazine, and pyrroledione derivatives (5, 6a-d, 7a-d, 8, 9, 10a-d, 11a-b, 12) with SOCl 2 , alcohols, amines, and hydrazines, respectively. The structures of synthesized compounds were clarified by 1 H NMR, 13 C NMR, IR, mass and elemental analysis methods.

One-Pot Synthesis of 2-Arylquinolines via in situ Acid Catalysis

“…Several typical applications of 2-arylquinolines are shown in Figure 1. Given the various properties of quinoline, many synthetic strategies have been developed, such as Skraup reaction 18 , Doebner-von Miller synthesis 19 , Pfitzinger synthesis 20 , Doebner synthesis 19 , Friedländer synthesis 21 , and Combes synthesis 22 . In addition to these traditional methods, it has sprung up that 2vinylanilines serve as a potential synthon for the construction of quinoline in recent years.…”