College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, People's Republic of China,
J Mol Model. 2013 Oct;19(10):4545-54. doi: 10.1007/s00894-013-1968-8. Epub 2013 Aug 17.
Density functional theory (DFT) was used to investigate the nickel- or nickel(0)/zinc- catalyzed decarbonylative addition of phthalic anhydrides to alkynes. All intermediates and transition states were optimized completely at the B3LYP/6-31+G(d,p) level. Calculated results indicated that the decarbonylative addition of phthalic anhydrides to alkynes was exergonic, and the total free energy released was -87.6 kJ mol(-1). In the five-coordinated complexes M4a and M4b, the insertion reaction of alkynes into the Ni-C bond occurred prior to that into the Ni-O bond. The nickel(0)/zinc-catalyzed decarbonylative addition was much more dominant than the nickel-catalyzed one in whole catalytic decarbonylative addition. The reaction channel CA→M1'→T1'→M2'→T2'→M3a'→M4a'→T3a1'→M5a1' →T4a1'→M6a'→P was the most favorable among all reaction pathways of the nickel- or nickel(0)/zinc- catalyzed decarbonylative addition of phthalic anhydrides to alkynes. And the alkyne insertion reaction was the rate-determining step for this channel. The additive ZnCl2 had a significant effect, and it might change greatly the electron and geometry structures of those intermediates and transition states. On the whole, the solvent effect decreased the free energy barriers.
密度泛函理论（DFT）被用于研究邻苯二甲酸酐与炔烃的镍或镍（0）/锌催化脱羰加成反应。所有的中间体和过渡态都在 B3LYP/6-31+G(d,p)水平下完全优化。计算结果表明，邻苯二甲酸酐与炔烃的脱羰加成反应是放热的，总自由能释放为-87.6 kJ mol(-1)。在五配位络合物 M4a 和 M4b 中，炔烃插入 Ni-C 键的反应先于插入 Ni-O 键的反应。镍（0）/锌催化的脱羰加成比镍催化的脱羰加成在整个催化脱羰加成中更为主导。邻苯二甲酸酐与炔烃的镍或镍（0）/锌催化脱羰加成的所有反应途径中，反应通道 CA→M1'→T1'→M2'→T2'→M3a'→M4a'→T3a1'→M5a1'→T4a1'→M6a'→P 是最有利的。并且炔烃的插入反应是这个通道的速率决定步骤。添加剂 ZnCl2 具有显著的影响，它可能极大地改变了那些中间体和过渡态的电子和几何结构。总的来说，溶剂效应降低了自由能垒。
