Activation of propane C-H and C-C bonds by a diplatinum cluster: potential energy surfaces and reaction mechanisms
Activation of propane C-H and C-C bonds by a diplatinum cluster: potential energy surfaces and reaction mechanisms
复制标题
二铂簇活化丙烷 C-H 和 C-C 键：势能表面和反应机制
DOI：
10.1007/s11224-013-0311-4
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发表时间：
2014-04-01
影响因子：
1.7
通讯作者：
Hu, Chang-Wei
中科院分区：
文献类型：
--
作者：
Ju, Ting-Yong;Yang, Hua-Qing;Hu, Chang-Wei
在BPW91/Aug-cc-pvtz，Lan12 Tz水平下，在单重态和三重态势能面上详细探讨了同核双金属铂簇合物催化C3H8的活化机理。C-H键断裂通道(脱氢和丙烯释放)在动力学上占优势，而C-C键断裂通道(去甲基化和乙烷释放)应被排除。此外，丙烯通道的释放在动力学上是有利的，而脱氢通道在热力学上是有利的。此外，C-H裂解中间体(Pt(2)H(2)C(3)H(6)b)和C-C裂解中间体(CH3HPt2CHCH3和CH3PtPtHC2H4)在热力学上都是优先的。C-H裂解中间体(Pt(2)H(2)C(3)H(6)b)在动力学上是有利的，而C-C裂解中间体(CH3HPt2CHCH3和CH3PtPtHC2H4)在动力学上受到阻碍。同核双金属铂原子对丙烷的反应活性高于铂原子，这与实验观察到的结果一致。
The activation mechanism of C3H8 catalyzed by the homonuclear bimetallic Pt-2 cluster has been detailedly explored on the singlet and triplet potential energy surfaces at BPW91/aug-cc-pvtz, Lanl2tz level. The C-H bond cleavage channel (dehydrogenation and the release of propylene) is kinetically predominant, whereas the C-C bond cleavage channel (demethanation and the release of ethane) should be ruled out. Furthermore, the release of propylene channel is kinetically favorable, while the dehydrogenation channel is thermodynamically preferable. Besides, both the C-H cleavage intermediate (Pt(2)H(2)C(3)H(6)b) and the C-C cleavage intermediates (CH3HPt2CHCH3 and CH3PtPtHC2H4) are thermodynamically preferred. The C-H cleavage intermediate (Pt(2)H(2)C(3)H(6)b) is kinetically favored, while the C-C cleavage intermediates (CH3HPt2CHCH3 and CH3PtPtHC2H4) are kinetically hindered. The homonuclear bimetallic Pt-2 cluster toward propane exhibits higher reactivity than the Pt atom, which is in good agreement with the experimental observation.