UC Riverside

The Larsen group focuses on accessing small molecules through one-step multi-component coupling reactions from inexpensive starting materials and a catalyst source. To this end, we have developed a solvent-free catalytic method to access various substituted 2-(2'-pyridyl)quinoline compounds in one step directly from inexpensive and commercially available materials. Purification is simple and is accomplished with the use of a short basic alumina plug and diethyl ether as the eluent. Current published methods to access these targets are plagued with lengthy multi-step reactions, hazardous reagents, and/or the wasteful use of solvents and other materials for purification purposes. In vitro studies of two substituted 2-(2'-pyridyl)quinoline compounds revealed cytotoxic activities in the A549 lung cancer cell line. In addition to the synthesis of various bidentate substituted 2-(2'-pyridyl)quinoline ligands, the neutral 5-coordinate gold(III) complexes of 6-phenyl-2-(2'-pyridyl)quinolines substituted at position 6 of the quinoline ring with fluorine, methyl, methoxy, and phenyl groups were also achieved. The x-ray crystallographic data revealed that the neutral complexes have distorted square pyramidal geometries. Furthermore, the cationic gold(III) complex of a 6-phenyl-2-(2'-pyridyl)quinoline with a methoxy moiety at position 6 of the quinoline ring was also synthesized with a tetrafluoroborate counter anion. The x-ray structure of this cationic complex revealed its distorted square planar geometry.