Density functional theory （DFT） calculations, at the B3LYP/6-311G＊＊ level of theory, were performed to study the reaction mechanism and potenti4the potential energy surface of the studied reactions was investigate...Density functional theory （DFT） calculations, at the B3LYP/6-311G＊＊ level of theory, were performed to study the reaction mechanism and potenti4the potential energy surface of the studied reactions was investigated. Our calculation results show that [2 ＋ 2] and [4 ＋ 4] reactions are concerted and synchronous processes; while [4 ＋ 2] reactions proceed via a concerted but asynchronous way in general. [2 ＋ 2] and [4 ＋ 2] reactions of germabenzenes and 1-germana- phthalene proceed much more easily than the corresponding [4 ＋ 4] reaction, both thermo- dynamically and kinetically; while most [4 ＋ 2] paths have lower activation barrier than the corres- ponding [2 ＋ 2] ones. As the number of six-membered aromatic rings in reactant molecules becomes larger, [2 ＋ 2], [4 ＋ 2] and [4 ＋ 4] reactions become easier to proceed. The influence of substituents at the Ge atom of germabenzenes on the potential energy surface of [2 ＋ 2] and [4 ＋ 2] reactions correlates with their electronic properties and volume. Solvent effect is not crucial for the potential energy surfaces of the studied reactions.展开更多
基金Henan Provincial Fundamental and Frontier Technological Research Program (No. 092300410207)
文摘Density functional theory （DFT） calculations, at the B3LYP/6-311G＊＊ level of theory, were performed to study the reaction mechanism and potenti4the potential energy surface of the studied reactions was investigated. Our calculation results show that [2 ＋ 2] and [4 ＋ 4] reactions are concerted and synchronous processes; while [4 ＋ 2] reactions proceed via a concerted but asynchronous way in general. [2 ＋ 2] and [4 ＋ 2] reactions of germabenzenes and 1-germana- phthalene proceed much more easily than the corresponding [4 ＋ 4] reaction, both thermo- dynamically and kinetically; while most [4 ＋ 2] paths have lower activation barrier than the corres- ponding [2 ＋ 2] ones. As the number of six-membered aromatic rings in reactant molecules becomes larger, [2 ＋ 2], [4 ＋ 2] and [4 ＋ 4] reactions become easier to proceed. The influence of substituents at the Ge atom of germabenzenes on the potential energy surface of [2 ＋ 2] and [4 ＋ 2] reactions correlates with their electronic properties and volume. Solvent effect is not crucial for the potential energy surfaces of the studied reactions.
