diaza-Wittig reaction) occur as a tandem process. RF-activated carbonyls are much more reactive in Wittig olefination of diazodicarbonyl and 1,3-dioxophosphazine molecules, than non-fluorinated acyl and aroyl carbonyl groups (RFCO ≫ COAlk, COAr), and as a result non-fluorinated diazodiketones and their phosphazines do not produce pyridazines under the same conditions.
两种方法被报告用于从含有氟烷基diazodiketones制备的3,4,6-三取代的
哒嗪:维悌希/施陶丁格/序列氮杂-Wittig和施陶丁格/维蒂希/二氮杂-Wittig反应。与通过初始
磷嗪相比,在第一阶段进行维蒂希反应可提高目标
哒嗪的收率。在这两种方法中,合成的最后阶段(
乙烯基膦嗪的形成和随后的diaza -Wittig反应)都是串联的过程。与未
氟化的酰基和芳酰基羰基相比,R F活化的羰基在重氮二羰基和1,3-二氧杂
磷嗪分子的Wittig烯化反应中具有更高的反应性(R FCO≫ COAlk,COAr),因此在相同条件下,非
氟化的重氮二酮及其膦嗪不会产生
哒嗪。