Benzonitrile → 7-Bromo-2-phenyl-[1,2,4]triazolo[1,5-A]pyridine

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A mixture of 2-amino-4-bromopyridine (5.00 g, 28.9 mmol), copper (I) bromide (207 mg, 1.44 mmol), 1,10-phenanthroline monohydrate (289 mg, 1.44 mmol), zinc iodide (923 mg, 2.89 mmol) and benzonitrile (125 mL) was heated in a 250-mL 3-necked flask to 130° C. During 23 h a gentle flow of air was bubbled through the reaction mixture (93% conversion, HPLC method cf. example 1.3). The dark brown suspension was then cooled to 0-5° C. and filtered. The filter cake was washed with TBME (50 mL) and dried to yield crude 7-bromo-2-phenyl-[1,2,4]triazolo[1,5-a]pyrdine (5.36 g, 51%) as a green solid with 76.0% purity (HPLC area-%, HPLC method cf. example 1.3). Major by-product: 7-Iodo-2-phenyl-[1,2,4]triazolo[1,5-a]pyridine (13.0%).

Herkunft & Nachweise