1-fluoro-1-lithioethenes bearing hydrogen, fluorine, phenyl, and/or dimethylphenylsilyl groups in the β-positions have been determined by a low-temperature 19F NMR spectroscopy. Some 1-fluoro-1-lithioethenes displayed an exceptionally low value of the trans-3JFF coupling constant. Stereoselectivity of carbenoid formation, as well as an effect of configuration on the stability is discussed.
已经通过低温19 F NMR光谱测定了在β位置带有氢,
氟,苯基和/或二甲基苯基甲
硅烷基的稳定化的1-
氟-1-
硫代
乙烯的半衰期和
氟原子位移。一些1-
氟-1- lithioethenes显示的异常低的值的反式- 3 Ĵ FF偶合常数。讨论了类
胡萝卜素形成的立体选择性以及构型对稳定性的影响。