Syntheses with the aid of lithiopyridines: Preparation of di‐pyridyl ketones, pyridyl‐phenyl‐carbinols and tri‐pyridyl‐carbinols

The preparation of phenyl pyridyl ketones by the action of 2‐lithiopyridine or 3‐lithiopyridine on benzoic anhydride, ethyl benzoate or benzonitrile is described: di‐pyridyl‐phenyl‐carbinols are produced by the further action of lithiopyridine on the ketones so obtained. The action of 2‐lithiopyridine on 2‐cyanopyridine or ethyl picolinate gives bis‐(pyridyl‐2) ketone; in a similar way bis‐(pyridyl‐3) ketone is prepared and some other di‐pyridyl ketones. By the action of 2‐lithiopyridine on bis‐(pyridyl‐2) ketone there is obtained tris‐(pyridyl‐2)‐carbinol; tris‐(pyridyl‐3)‐carbinol has been synthesised in a similar way.