Trifluoroacetic acid → N1-isopropyl-4-chloro-2-nitroaniline

Participants

Reaction Steps

4-chloro-2-nitroaniline (8.6 g; 0.05 mole), 2,2-dimethoxypropane (10.0 ml; 0.9 mole) and trifluoroacetic acid [TFA] (4.0 ml; 0.005 moles) were dissolved in toluene (100 ml) and stirred for 1 hr. BH3 pyridine (5.0 ml; 0.05 moles) was added in 1.0 ml increments. The reaction was exothermic, and the reaction progress was monitored by tlc 40%EtOAc/Hexane. Additional TFA, BH3 * pyridine and 2,2-dimethoxypropane were added until the tlc indicated that the 4-chloro-2-nitroaniline was consumed. The reaction mixture was placed on a bed of silica and eluted with toluene. The product was the first major component to elute, which produced 8.4 g (78%) of a yellow crystalline solid.

Provenance & Evidence