Preparation of Polyfunctionalized Aromatic Nitriles from Aryl Oxazolines.

ABSTRACT

A selective ortho,ortho'-functionalization of readily available aryl oxazolines by two successive magnesiations with sBu2 Mg in toluene followed by trapping reactions with electrophiles, such as (hetero)aryl iodides or bromides, iodine, tosyl cyanide, ethyl cyanoformate or allylic bromides (39 examples, 62-99 % yield) is reported. Treatment of these aryl oxazolines with excess oxalyl chloride and catalytic amounts of DMF (50 °C, 4 h) provided the corresponding nitriles (36 examples, 73-99 % yield). Conversions of these nitriles to valuable heterocycles are reported, and a tentative mechanism is proposed.