Dichloromethane → 2-(trichloromethyl)-1H-imidazole

Participants

Reaction Steps

To a suspension of 4-chloro-7H-pyrrolo[2,3-d]pyrimidine-5-carbaldehyde oxime (E-4) (865 mg, 4.40 mmol, 1.0 eq) in DCM (20 mL), thionyl chloride (3.1 mL, 43.7 mmol, 10.0 eq) is added and the resulting mixture is stirred at RT overnight. The reaction mixture is concentrated in vacuo. The residue is suspended in water (60 mL) and saturated aqueous NaHCO3 is added to adjust the pH to 4. The solid is collected by filtration, rinsed with water followed by ethyl acetate to afford a first portion of product. The filtrate is then extracted with ethyl acetate (50 mL×3). The combined organic layers are washed with brine, dried over Na2SO4 and filtered. The filtrate is concentrated in vacuo and the residue is combined with the first portion of product. The product is then re-crystallized in ethyl acetate/hexanes (1:1) and dried in vacuo to afford the final product, 4-chloro-7H-pyrrolo[2,3-d]pyrimidine-5-carbonitrile (E-5) as a pale solid.

Provenance & Evidence