Azaquinolizine類の合成研究(第4報) : 2,3,4,4a, 5,6,7,8-Octahydro-1H-pyrido[1,2-b]pyrimidineの合成
1968 年 88 巻 2 号 p. 216-218
詳細
1968 年 88 巻 2 号 p. 216-218
Reaction of picolyllithium with bromoacetaldehyde acetal gave 2-pyridylpropionaldehyde acetal (I), whose reduction over platinic oxide catalyst at room temperature under a high pressure yielded β-(2-piperidyl) propionaldehyde acetal (II). The N-nitroso compound (III) derived from II was reduced to the corresponding N-amino compound (IV) with lithium aluminium hydride. An alcoholic solution of IV was heated with oxalic acid, resulting in the cyclization of (IV) to 3, 4, 5, 6, 7, 8-hexahydro-4aH-pyrido-[1, 2-b] pyridazine (V). Acetic acid solution of V absorbed one mole of hydrogen over platinic oxide catalyst to give 2, 3, 4, 4a, 5, 6, 7, 8-octahydro-1H-pyrido [1, 2-b] pyridazine (VI).
