作者:Hajime Kuwabara、Yoshihiro Ushigoe、Masatomo Nojima
DOI:10.1039/p19960000871
日期:——
Carbonyl oxides, derived from the ozonolyses of vinyl ethers, readily undergo [3 + 2] cycloadditions with acyl cyanides affording the corresponding cyano-substituted 1,2,4-trioxolanes in isolated yields of 34–88%. In competition experiments, a relative order of reactivity of the carbonyl oxide trapping agents was tentatively deduced; trifluoroacetophenone > α,α-diphenyl-N-methylnitrone (N-methyldiphenyl-methylideneamine N-oxide) > benzoyl cyanide > methyl benzoylformate > α,α,N-triphenylimine [N-(diphenylmethylidene)aniline] benzaldehyde. As expected from the electron-withdrawing ability of the cyano group, 3-cyano-3-phenyl-1,2,4-trioxolane oxidized not only triphenylphosphine but also methyl p-tolyl sulfide and 2,3-dimethylbut-2-ene very easily.
乙烯基醚臭氧分解产生的羰基氧化物很容易与酰基氰化物发生[3 + 2]环加成反应,生成相应的氰基取代的 1,2,4-三氧杂环戊烷,分离产率为 34-88%。在竞争实验中,初步推断出了羰基氧化物捕获剂的相对反应顺序:三氟苯乙酮 > α,α-二苯基-N-甲基硝酮(N-甲基二苯基亚甲基胺 N-氧化物) > 苯甲酰氰 > 苯甲酰甲酸甲酯 > α,α,N-三苯基亚胺 [N-(二苯基亚甲基)苯胺] 苯甲醛。正如氰基的吸电子能力所预期的那样,3-氰基-3-苯基-1,2,4-三氧杂环戊烷不仅很容易氧化三苯基膦,还很容易氧化甲基对甲苯硫醚和 2,3-二甲基-2-丁烯。