Cyanomethylene and Nitromethylene Derivatives of Squaric Acid The Wittig-Horner reaction of diethyl cyanomethane phosphonate with various squaric acid diamides leads to novel push-pull substituted cyclobutenes 5, 6, and 7. In contrast, the diaminoquadrain 9, by way of nucleophilic substitution, yields the dianion 11. In addition the first synthesis of pseudooxocarbor anions with nitromethylene groups is described.
氰甲叉和硝
甲叉衍
生物的
方酸 二乙基氰甲叉膦酸酯与各种
方酸二酰胺的Wittig-Horner反应产生新型推-拉取代的
环丁烯5、6和7。相比之下,通过亲核取代反应,二
氨基
方酸9生成二负离子11。此外,还描述了首例含有硝
甲叉基团的假氧杂
硼烷负离子的合成。