Phosphorus sulfide (P2S5) → HCID 14390444, compound

Participants

Reaction Steps

A mixture of 2-(4-chlorophenyl)-3H-imidazo[4,5-b]pyridine-3-acetamide (3.44 g, 0.012 mole) and phosphorus pentasulfide (1.47 g, 0.0033 mole) in 150 ml of dry acetonitrile (dried over molecular sieves) was heated at reflux for 3 hr. The reaction mixture was filtered and washed with boiling acetonitrile. The solid residue in the flask was treated with boiling methanol and filtered. The methanol and acetonitrile filtrates were combined and evaporated to dryness. The residue was treated with acetone and filtered through a silica gel filter funnel. The filtrate was treated with Florisil®, filtered, and evaporated to dryness. The residue was treated with acetone, applied to a silica gel column (7×15 cm), and eluted with acetone. The appropriate fractions were combined and evaporated. The residue was dissolved in hot methanol, treated with activated charcoal, and filtered through a Celite pad. The filtrate was concentrated to initiate crystallization. The mixture was diluted with water and ice, then filtered to collect the precipitate which was washed with water. The solid was dried under high vacuum overnight at room temperature, then at 55° C. for 5 hr. to give 0.31 g product (8.3%), mp 226°-29° C. with decomposition.

Provenance & Evidence