Li Laicai, Wang Wei, Wang Xiaolan, Zhang Lin
College of Chemistry and Material Science, Sichuan Normal University, Chengdu, 610066, People's Republic of China.
J Mol Model. 2016 Aug;22(8):186. doi: 10.1007/s00894-016-3039-4. Epub 2016 Jul 21.
Cinnamaldehyde (CAL) belongs to the group of aromatic α,β-unsaturated aldehydes; the selective hydrogenation of CAL plays an important role in the fine chemical and pharmaceutical industries. Using Ptn clusters as catalytic models, we studied the selective hydrogenation reaction mechanism for CAL catalyzed by Ptn (n = 6, 10, 14, 18) clusters by means of B3LYP in density functional theory at the 6-31+ G(d) level (the LanL2DZ extra basis set was used for the Pt atom). The rationality of the transition state was proved by vibration frequency analysis and intrinsic reaction coordinate computation. Moreover, atoms in molecules theory and nature bond orbital theory were applied to discuss the interaction among orbitals and the bonding characteristics. The results indicate that three kinds of products, namely 3-phenylpropyl aldehyde, 3-phenyl allyl alcohol and cinnamyl alcohol, are produced in the selective hydrogenation reaction catalyzed by Ptn clusters; each pathway possesses two reaction channels. Ptn clusters are more likely to catalyze the activation and hydrogenation of the C = O bond in CAL molecules, eventually producing cinnamic alcohol, which proves that Ptn clusters have a strong reaction selectivity to catalyze CAL. The reaction selectivity of the catalyzer cluster is closely related to the size of the Ptn cluster, with Pt14 clusters having the greatest reaction selectivity. Graphical Abstract The reaction mechanism for the selective hydrogenation reaction ofcinnamaldehyde catalyzed by Ptn clusters was studied by densityfunctional theory. The reactionselectivity of cluster catalyzer was concluded to be closely related to the size of Ptn clusters, with Pt14 clusters having the greatest reaction selectivity.
肉桂醛（CAL）属于芳香族α,β-不饱和醛类；CAL的选择性氢化在精细化工和制药行业中起着重要作用。我们以Ptn团簇为催化模型，采用密度泛函理论中的B3LYP方法，在6-31+G(d)水平（Pt原子采用LanL2DZ赝势基组）研究了Ptn（n = 6、10、14、18）团簇催化CAL的选择性氢化反应机理。通过振动频率分析和内禀反应坐标计算证明了过渡态的合理性。此外，应用分子中的原子理论和自然键轨道理论讨论了轨道间的相互作用和键合特征。结果表明，在Ptn团簇催化的选择性氢化反应中生成了三种产物，即3-苯基丙醛、3-苯基烯丙醇和肉桂醇；每条反应路径都有两个反应通道。Ptn团簇更倾向于催化CAL分子中C=O键的活化和氢化，最终生成肉桂醇，这证明Ptn团簇对催化CAL具有很强的反应选择性。催化剂团簇的反应选择性与Ptn团簇的尺寸密切相关，其中Pt14团簇的反应选择性最大。图形摘要 采用密度泛函理论研究了Ptn团簇催化肉桂醛选择性氢化反应的机理。得出团簇催化剂的反应选择性与Ptn团簇的尺寸密切相关，其中Pt14团簇的反应选择性最大。
