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用量子化学密度泛函理论的B3LYP方法，对[Pd（dppp）（H2 O）2]（BF4）2催化7三甲基硅基4，4二乙酸乙酯基6炔2庚酮合成环外烯烃的反应机理进行了研究．对Pd原子采用LanL2DZ赝势基组外加一套 f轨道极化函数，其极化系数为1．472；对C ，Si ，P ，O和H用6311G（d ，p）基组．研究表明，前催化剂与乙醇溶剂反应生成的新催化剂催化链状炔酮加氢环化生成环外烯烃的最优势路径包括炔基的活化、氢活化和加氢过程、C—C环化反应、水分子上的氢转移以及催化剂解离等步骤，C—C环化反应是该机理中的速率控制步．新的 Pd （II ）金属络合物催化作用的本质在于，Pd（II）与炔基配位，使吉布斯自由能下降64．10 kJ／mol ，电荷分布发生改变，叁键C（1）≡C （2）被削弱，炔基活化．“,”By using the B3 LYP of density functional theory(DFT ) ,the synthesis mechanism of exocyclic olefin via [Pd(dppp)(H2 O)2 ](BF4 )2 catalyzed chain acetylenic ketone was studied .The Pd atoms was cal‐culated with LanL2DZ pseudopotential basis sets by adding a set of f orbital polarization function ,which coefficient was 1 .472 ;C ,Si ,P ,O and H with 6‐311G (d ,p) basis set were calculated ,respectively .The re‐sults show that the optimal path of new catalysts generated from the reaction of the former catalyst and ethanol solventreaction catalyze chain acetylenic ketone involves five steps :activation of the alkynyl ,and hydrogen ,hydrogenation process ,C-C cyclization reaction ,hydrogen transfer of w ater molecules ,and dis‐sociation of catalyst .C-C cyclization reaction is the rate controlling step in the mechanism .The essence of the new Pd (II) metal complexe catalysts is that its coordination with alkynyl ,decreases the Gibbs free en‐ergy to 64 .10 kJ/mol ,and changes the charge distribution ,leading to thnf three bond C(1)≡C(2) is weak‐ened ,and the alkynyl is activated .