Radical addition reactions. Part II. The addition of ethyl cyanoacetate to conjugated olefins
作者:R. L. Huang、Chong-Oon Ong、S. H. Ong
DOI:10.1039/j39680002217
日期:——
The addition of ethyl cyanoacetate, catalysed by t-butyl peroxide at 155—160°, to a series of conjugated olefins XCH:CHY, namely dimethyl fumarate (X = Y = CO2Me), methyl crotonate (X = Me, Y = CO2Me), β-methylstyrene, methyl cinnamate, benzylideneacetone, and cis- and trans-cinnamonitrile (X = Ph, Y = Me, CO2Me, Ac, or CN, respectively), gives mainly the 1 : 1-adduct, XCHR·CH2Y (R = CH(CN)·CO2Et)
将叔丁基过氧化氢在155-160°催化的氰基乙酸乙酯添加到一系列共轭烯烃XCH:CHY中,即富马酸二甲酯(X = Y = CO 2 Me),巴豆酸甲酯(X = Me,Y = CO 2 Me),β-甲基苯乙烯,肉桂酸甲酯,亚苄基丙酮,顺式和反式肉桂腈(分别为X = Ph,Y = Me,CO 2 Me,Ac或CN),主要产生1:1加合物,在前两种情况下为XCHR·CH 2 Y(R = CH(CN)·CO 2 Et),在其他情况下为XCH 2 ·CHRY,产率分别为26、53、42、31、16、26和分别为20%。顺式-肉桂腈异构化为反式反应条件下的β-异构体被解释为由于加成步骤的可逆性。但是,在同一丁腈中添加丁醛不会发生这种情况,从而得到PhCH 2 ·CH(CN)·COPr n(40%)。