Syntheses, with the aid of (4‐pyridyl)‐magnesium chloride, of 4‐lithiopyridine and of 3‐lithioquinoline

Abstract

Abstract 4‐Chloropyridine can be converted for about 70% into a complex magnesium compound, which reacts in the manner of a Grignard compound with aldehydes or ketones, forming (4‐pyridyl)‐carbinols; with orthoformic ester, (4‐pyridyl)‐methanal‐acetal is formed. The reaction of 4‐lithiopyridine with benzophenone and with ethyl benzoate respectively leads to the formation of (4‐pyridyl)‐diphenyl‐carbinol and to bis‐(4‐pyridyl)‐phenyl‐carbinol respectively. With aromatic nitriles, (4‐pyridyl)‐aryl ketones are formed. The reactions of 4‐lithiopyridine with cyanopyridines or with pyridine‐carboxylic esters lead to the formation of bis‐pyridyl ketones, e.g. , bis‐(4‐pyridyl) ketone. Quinolyl ketones are obtained by starting from 3‐lithioquinoline.