Trityl chloride → 4-Chloromethyl-2-tritylaminothiazole

Beteiligte Stoffe

Reaktionsschritte

A solution of 2-amino-4-chloromethylthiazole hydrochloride (3.701 g), trityl chloride (11.15 g), triethylamine (10.5 ml) and dimethylaminopyridine (10 mg) in chloroform (150 ml) was stirred at room temperature. After 23 h the reaction mixture was diluted with chloroform (150 ml) and then washed with 5% aqueous sodium hydrogen carbonate solution (2×50 ml) and brine (50 ml), dried (MgSO4) and evaporated to an orange gum. The gum was triturated with diethyl ether to give a pale brown solid. The liquors from the trituration were diluted with ethyl acetate (250 ml) and washed with M-hydrochloric acid (3×60 ml), water (60 ml), and brine (30 ml) dried (MgSO4) and evaporated to a pale brown foam. The triturated solid was treated in the same manner as the liquors to give a pale brown foam. The two foams were combined and subjected to column chromatography on silica developing and eluting with ethyl acetate-petrol, 1:9 and gave an off white solid (3.241 g). A portion (240 mg) of the solid was crystallised twice from ethyl acetate-petrol to give off white crystals of the title thiazole (206 mg), m.p. 139°-140° C., λmax (EtOH) 267.5 nm (ε 8,050).

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