Nitrilium salts 1 react with α,β-unsaturated ketones 7a and aldehydes 7f,h,j to furnish either 4H-1,3-oxazinium salts 5a-e or 6H-1,3-oxazinium salts 11f-i or N-acyl-1-azonia-1,3- butadiene salts 10j,k. The formation of these products is explained by a multistep reaction sequence starting with a [2+2] cycloaddition of the carbonyl double bond to the nitrilium triple bond. The constitution of 6H-1,3-oxazinium hexachloroantimonate 11i is confirmed by an X-ray structural analysis.
硝盐 1 与 α,β-不饱和酮 7a 和醛 7f,h,j 反应,生成 4H-1,3-恶嗪盐 5a-e 或 6H-1,3-恶嗪盐 11f-i 或 N-酰基-1-azonia-
1,3-丁二烯盐 10j,k。这些产物的形成可以通过多步反应顺序来解释,该反应顺序以羰基双键与腈鎓三键的[2+2]环加成开始。通过X射线结构分析确认了6H-1,3-恶嗪鎓六氯
锑酸盐11i的构成。