3-difluoroazulenes were synthesized for the first time by the electrophilic fluorination of azulenes with N-fluoro reagents. Selective preparation of 1-fluoroazulenes were performed by the fluorination of methyl azulene-1-carboxylates, followed by demethoxycarbonylation in 100% H3PO4. 2-Substituted azulenes were fluorinated in higher yields. In the 1H NMR of 1-fluoroazulene, long-range JFH values were
1-
氟-和1,3-二
氟-和1,3-二
氟-和1-二
氟-和1,3-二
氟- azulenes 是第一次通过用N-
氟试剂对azulenes 进行亲电
氟化来合成。1-
氟丁烯的选择性制备是通过甲基 azulene-1-carboxylates 的
氟化,然后在 100% H3PO4 中脱甲氧基羰基化来进行的。2-取代的
芘以更高的产率被
氟化。在 1-
氟芴的 1H NMR 中,与
1-氟萘相比,在 H-2 和 H-8 处未观察到长程 JFH 值。由于所谓的 +Iπ 效应,1-
氟原子会导致薁的可见光吸收发生显着的红移。