Vanderhoydonck Bart, Stevens Christian V
Department of Organic Chemistry, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, B-9000 Ghent, Belgium.
J Org Chem. 2005 Jan 7;70(1):191-8. doi: 10.1021/jo0488661.
Several 1-phosphono-2-aza-1,3-butadienes, 1 and 13-20, were evaluated in the reaction with different enolate-type nucleophiles to induce addition at the 1- or the 4-position of the azadiene. 1-Phosphono-2-azadienes 1 react with sodium malonate at the 1-position, leading to the formation of bisenamines 12 after elimination of the phosphonate moiety. On the contrary, sodium malonate adds at the 4-position of 1-aryl-1-phosphono-2-azadienes 14-19 when the azadienes bear a halogenated phenyl substituent, and the resulting addition products 21-26 are easily transformed into the corresponding phosphonylated gamma-lactams 35-40. The regioselectivity of the addition is explained by reversal of polarization of the azadiene due to the electron-withdrawing character of the halogenated phenyl substituents.
研究了几种1-膦酰基-2-氮杂-1,3-丁二烯（1以及13 - 20）与不同烯醇盐型亲核试剂的反应，以诱导在氮杂二烯的1位或4位发生加成反应。1-膦酰基-2-氮杂二烯1与丙二酸二钠在1位反应，在消除膦酸酯部分后生成双烯胺12。相反，当氮杂二烯带有卤代苯基取代基时，丙二酸二钠在1-芳基-1-膦酰基-2-氮杂二烯14 - 19的4位加成，所得加成产物21 - 26可容易地转化为相应的膦酰化γ-内酰胺35 - 40。由于卤代苯基取代基的吸电子特性导致氮杂二烯极化反转，从而解释了加成反应的区域选择性。
