Dication species stabilized by heteroazulenes: synthesis and properties of 1,3- and 1,4-bis[bis(2-oxo-2H-cyclohepta[b]furan-3-yl)methyliumyl]-, bis[bis(1,2-dihydro-N-methyl-2-oxocyclohepta[b]pyrrol-3-yl)methyliumyl]benzene, and their related dications
作者:Shin-ichi Naya、Makoto Nitta
DOI:10.1039/b009373o
日期:——
A general synthetic route to a novel type of heteroazulene analogue of exceptionally stable dimethyliumbenzenes (16a–c·2PF666−−− and 17a–c·2PF666−−−) bearing 1,3-di- and 1,4-dimethylium groups substituted with four 2H-cyclohepta[b]furan-2-one 9a, four 1,2-dihydro-N-methylcyclohepta[b]pyrrol-2-one 9b, and two 9a and two 9b, is reported. The synthetic method is based on a single and stepwise TFA-catalyzed
合成新型的具有稳定的二甲基苯(16a–c · 2PF 6 66 − −和17a–c · 2PF 6 66 − − −)的新型杂氮烯类似物的一般合成路线,带有1,3-di-和1,4-被四个取代的二甲基鎓基团2 H-环庚[ b ]呋喃-2-酮 9a,41,2-二氢-N-甲基环庚[ b ]吡咯-2-酮 报道了图9b,以及两个9a和两个9b。合成方法基于单步逐步TFA催化的亲电子试剂芳香取代在杂腈9a和9b上间苯二甲醛 和 对苯二甲醛得到相应的1,3-和1,4-二甲基苯衍生物,然后用DDQ进行氧化氢抽象,随后通过使用NaHCO 3交换抗衡阴离子。HPF 6解决方案。尽管16a–c和17a–c具有特殊性质,但由于杂腈单元的稳定作用,它们仍显示出较高的稳定性和较大的p K R +值。但是,我们无法分别确定p K R +和p K R ++的值。因此,p K R +值对应于用于形成中和的指示剂和半中和的单阳离子的pH值的平均值。电化学的减少