メチルピリミジン誘導体のVilsmeier反応

抄録

The Vilsmeier reaction (POCl₃ and dimethylformamide) on the active methyl group in pyrimidine derivatives was examined with 4-methyl-2-phenyl-(IIIa), 4-methyl-6-phenyl-(IIIb), 2-methyl-4-phenyl-(IIIc), and 4-methyl-pyrimidine (IIId). These compounds all afforded the corresponding malonaldehyde compounds (Va-d) in a fair yield. In the case of IIId, a minute amount of 4-aminopyridine-3-aldehyde (VIII), formed by the recyclization of the ring, was obtained. Similar reaction was carried out with 2, 6-dimethyl-4-pyrimidone (IIIf), and 4-chloro-2, 6-dimethyl-(IIIg), and 2, 6-dimethyl-4-dimethylamino-pyrimidine (IIIh). IIIf and IIIg afforded 4-dimethylamino-2-methylpyrimidine-6-malonaldehyde (XI) produced by the attack on the methyl group in 6-position, and IIIh afforded the isomer (XII) of XI formed by the attack on the methyl group in 2-position.