Phosphorodichloridic acid, phenyl ester → 2-Chloro-5-iodo-3-nitropyridine

Participants

Reaction Conditions

Reaction Steps

A suspension of 5-iodo-3-nitro-pyridin-2-ol (20 g) in phenyl dichlorophosphate (60 ml) was heated at 180° C. for 30 minutes whereby a brown solution was obtained. The solution was allowed to cool then poured onto ice/water, neutralised by a portionwise addition of solid sodium hydrogen carbonate and extracted with ethyl acetate (300 ml) which was then washed twice with 5% sodium hydrogen carbonate solution (250 ml). The organic layer was dried (MgSO4), and evaporated to give a pale brown solid. The solid was stirred in isohexane for 2 h, filtered off, washed with isohexane and dried to afford the title compound (18.4 g).

Provenance & Evidence