作者:Daniel W. J. Moloney、Ming Wah Wong、Robert Flammang、Curt Wentrup
DOI:10.1021/jo9701288
日期:1997.6.1
Cyanoketene (8) is generated in high yields on flash vacuum thermolysis (FVT) of suitably substituted Meldrum's acid derivatives (5-[(alkylamino)(methylthio or alkylamino)methylene]-2,2-dimethyl-1,3-dioxane-4,6-diones) (3e-j), and also on FVT of cyanoacetic acid derivatives 9e,f,g,j,k,m. The major reaction pathway from 3 proceeds via ketenimines 6 and (alkylimino)propadienones 7, the latter undergoing
氰基乙烯酮(8)通过闪蒸真空热解(FVT)适当取代的麦德鲁姆酸衍生物(5-[((烷基氨基)(甲硫基或烷基氨基)亚甲基] -2,2-二甲基-1,3-二恶烷-4)高产率生成,6-二酮)(3e-j),以及氰基乙酸衍生物9e,f,g,j,k,m的FVT。3的主要反应途径是通过烯酮亚胺6和(烷基亚氨基)丙二烯酮7进行的,后者进行逆烯反应至8。次要途径是通过亚氨基酮烯4e,h和氧烯酮5e,h,它们进行逆烯反应。 9.所有中间体均通过Ar矩阵FTIR和串联质谱(碰撞活化MS)进行表征。还报道了用亲核试剂捕获4、5和8。1,3-X的优先级会超过1,酰亚胺基乙烯酮12(X = SMe或NMe(2))中的5-H位移已通过计算得出的激活势垒得到证实。纯的氰基烯酮具有很高的反应活性,在80 K或更低的温度下会发生反应,这归因于低洼的烯酮LUMO的可用性。氰基烯(Ar,14 K)的IR光谱主要受2163(s; C =