Ethyl Acetate → 2-(4-chlorophenyl)-1-methyl-5-(trifluoromethyl)-1H-pyrrole-3-carbonitrile

Participants

Reaction Conditions

Reaction Steps

A solution of N-(p-chloro-α-cyanobenzyl)-2,2,2-trifluoro-N-methylacetamide (13.8 g, 0.05 mol) in toluene is treated with tetrafluoroboric acid-diethyl etherate (10.5 g as is, 8.9 g real, 0.055 mol) at room temperature, heated to 60° C., treated with 2-chloroacrylonitrile (6.9 g, 0.075 mol) over a 25 minute period, held for 2 to 2.5 hours at 60° C., cooled and treated with ethyl acetate. The resultant solution is washed with water and concentrated to give a waxy residue. Flash column chromatography of the residue on silica gel packed with 15% ethyl acetate in heptane and eluted with 20% ethyl acetate in heptane gives the title product as pale yellow crystals, 3.1 g (22% yield), mp 129°-130° C., identified by 1H, 13C, and 19F NMR analyses.

Provenance & Evidence