Keteneおよびその誘導体の研究(第42報) : 1-Acetoacetylaziridine誘導体の環拡大反応

抄録

Reaction of diketene with ethylenimine (Ia), 2, 2-dimethylaziridine (Ib), 2, 2-diphenyl-3-methylaziridine (Ic), ethylaziridine-2-carboxylate (Id), aziridine-2-carboxamide (Ie), and 2-benzoyl-3-phenylaziridine (If) afford the corresponding 1-acetoacetylaziridines (II) in a good yield. Treatment of II with sodium iodide or conc. sulfuric acid results in their isomerization to 2-acetonyl-2-oxazoline derivatives (III or IV). Isomerization of IIb-e preferentially occurs only in one direction but treatment of IIf with sodium iodide produces IIIf and IVf at the same time. Warming of IIf in benzene results in its isomerization to 6-methyl-2-phenacyl-3, 4-dihydro-2H-1, 3-oxazin-4-one (XVII), while treatment of IIf with sodium ethoxide gives 3-acetyl-5-benzyl-4-phenylpyrrolenin-2-one (XIX).