In a
250-ml. three-necked flask equipped with a
reflux condenser and a
gas-inlet tube are placed
45.6 g. (0.4 mole) of 2-chloropyrimidine (p. 182) and
150 ml. of absolute ethanol. The mixture is refluxed for 6 hours while anhydrous
dimethylamine is bubbled into the solution (Note
1). The solution is cooled, and
100 ml. of ethanol is removed by distillation using a
water aspirator. The residue is chilled in an
ice bath for 1 hour, and
75 ml. of ether is added to cause precipitation of
dimethylamine hydrochloride. After the removal of
dimethylamine hydrochloride and solvent, the residue is distilled at reduced pressure from a
Claisen flask (Note
2). The fraction boiling at
85–86°/28 mm. is collected; yield
40–42.5 g. (
81–86%),
n25D 1.5420 (Note
3).