Phosphorus oxychloride → 4-Chloro-5-iodo-2,6-dimethylpyrimidine

Beteiligte Stoffe

Reaktionsschritte

A mixture of 2,6-dimethyl-5-iodo-4-hydroxypyrimidine (24.5 g, 0.098 mol), phosphorus oxychloride (30.0 g, 0.196 mol) and toluene (200 mL) was heated under reflux for 1 h. The mixture was concentrated and ice water (100 mL) was added. The pH was adjusted to 5 with 2.5N NaOH and the mixture was extracted with CH2Cl2. The combined extracts were washed with brine, dried MgSO4), and concentrated to give 24.6 g of a brown solid. The crude product was combined with 26.0 g of similarly prepared material and filtered through a short column of silica gel eluted with CH2Cl2 to give 33.8 g (62%) of product as a yellow solid. An analytical sample was recrystallized from hexane/CH2Cl2, mp 62°-64° C.

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