Methanol → Methyl 3-(cyanomethyl)benzoate

Participants

Reaction Steps

Methyl-3-bromomethylenebenzoate (5.0 g, 0.022 mol, Ryan Chemicals (Maybridge)), dry potassium cyanide (2.9 g, 0.044 mol), and 18-crown-6 (0.5 g, 0.0018 mol) was added to ~50 mL acetonitrile in a 100-mL round-bottom flask. The mixture was vigorously stirred for 24 h at room temperature. The reaction was monitored by TLC (Bakerflex) in dichloromethane, 2% methanol, and 5% methanol/dichloromethane. A heavy white precipitate (KBr) was removed by filtration. The filtrate was concentrated to 1/3 of the original volume and water was added until the final volume was ~100 mL. The yellow solution was added to a 250-mL separatory funnel and was extracted with dichloromethane until the organic phase was colorless and then twice more. The organic layers were combined and dried with magnesium sulfate. The drying agent was removed by filtration and the solvent was concentrated to a light yellow oil. The oil was dissolved into an equal volume of ether and was added to a 15×2.5 cm column of TLC grade silica gel and eluted with ether. The progress of the column was followed with a hand-held UV lamp. When the faster-running impurities had eluted, the product was collected and the solvent was concentrated leaving a light yellow oil. Though this oil was pure by TLC, the product was distilled (101.5° C. at 0.05 mm Hg) leaving 3.5 g (92%) of methyl-3-cyanomethylbenzoate.

Provenance & Evidence