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一般烯烃容易发生亲电加成反应,而全氟或多氟(卤)型烯烃容易发生亲核加成反应~([3])但介于典型烯烃(如乙烯)及典型全氟烯烃(如四氟乙烯)之间的偏氟乙烯是否能进行亲核加成,至今尚无答案。偏氟乙烯分子一端的两个氟原子的吸电子诱导效应,使双键的电子密度下降,而且两个氟原子的p电子对与双键的π电子间的p-π排斥作用使该双键发生极化,在CF_2一端的碳上出现δ~(+[4,5]),因此我们认为偏氟乙烯应该可以发生亲核加成,且在CF_2一端接受亲核进攻。为此,我们选用了最典型的亲核试剂t-C_4H_9O~-、i-C_3H_7O~-、n-C_3H_7O~-、C_2H_5O~-及CH_3O~-
General olefins are susceptible to electrophilic addition reactions, while perfluoro or polyfluoro (halo) type olefins are prone to undergo nucleophilic addition reactions (3) but with typical olefins (such as ethylene) and typical perfluoroolefins Tetrafluoroethylene) between the vinylidene fluoride nucleophilic addition can be carried out, so far no answer. The electron-withdrawing effect of two fluorine atoms at one end of a vinylidene fluoride molecule decreases the electron density of the double bond and the p-π repulsion between the p-electron pair of the two fluorine atoms and the π-electron of the double bond makes the double bond Polarization occurs and δ ~ (+ [4,5]) appears on the carbon at one end of CF_2, so we believe that vinylidene fluoride should undergo nucleophilic addition and accept nucleophilic attack at one end of CF_2. Therefore, we chose the most typical nucleophiles t-C_4H_9O ~ -, i-C_3H_7O ~ -, n-C_3H_7O ~ -, C_2H_5O ~ - and CH_3O ~