Phosphorus oxychloride → 2,7-Dichloro-5-cyclopropyl-thiazolo[4,5-d]pyrimidine

Participants

Reaction Steps

To a solution of the compound (0.82 g) obtained in Step 4 in phosphorus oxychloride (2.5 ml) was added N,N-diisopropylethylamine (0.25 ml) under ice-cooling, and the mixture was heated under reflux for 2 hr. The reaction mixture was concentrated under reduced pressure, toluene was added to the residue, and the mixture was concentrated again under reduced pressure. The obtained residue was dissolved in ethyl acetate, poured into ice water and partitioned. The organic layer was washed successively with saturated aqueous sodium hydrogen carbonate solution and saturated brine, dried over anhydrous sodium sulfate, filtrated, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate:n-hexane=1:8) to give the title compound (0.79 g).

Provenance & Evidence