Faculty of Chemistry, University of Wrocław, 14 F. Joliot-Curie, 50-383, Wrocław, Poland.
, Wrocław, Poland.
J Mol Model. 2020 Mar 7;26(4):73. doi: 10.1007/s00894-020-4333-8.
The formation of CO from CO monomolozonide is a three-step process with the isomer dependent last step leading either to c,c-CO epoxide or d,d-CO oxidoannulene. The process involves the open intermediate (first O-O then C-C/C-C bonds broken), oxidoannulene-like structure intermediate (new C-O/C-O bond formed) and finally the oxide product. On the formation of c,c-CO isomer, the final release of O is followed by the restoration of C-C bond, which stabilizes the product. Neither C-C bond is restored nor the total energy essentially lowered upon d,d-CO formation. At all steps of the studied process, the four CC bonds adjacent to C-C or C-C bond, respectively, play a crucial role donating or withdrawing the necessary electron density. C(O)O products, with O bridging one of the bonds adjacent to the parent C-C/C-C one, may compete with the oxide products. The OO bond in such structures is weak as suggested by its low electron population. For both c,c-CO and d,d-CO, the shape of the potential energy surfaces (0 K) and the related, reported earlier, room temperature-free energy surfaces differ. Graphical abstract.
一氧化碳单重态与臭氧的反应生成一氧化碳是一个分三步进行的过程,最后一步取决于异构化,产物可以是 c,c-CO 环氧化物,也可以是 d,d-CO 氧杂环辛二烯。该过程涉及开环中间体(首先是 O-O 键断裂,然后是 C-C/C-C 键断裂)、类氧杂环辛二烯结构中间体(形成新的 C-O/C-O 键)和最终的氧化物产物。在生成 c,c-CO 异构体的过程中,最后释放 O 原子后 C-C 键得到恢复,从而稳定产物。在生成 d,d-CO 时,既没有恢复 C-C 键,也没有降低总能量。在研究过程的所有步骤中,分别与 C-C 或 C-C 键相邻的四个 CC 键在提供或获取必要的电子密度方面起着至关重要的作用。O 桥接与母体 C-C/C-C 相邻的一个键的 C(O)O 产物可能与氧化物产物竞争。这些结构中的 OO 键很弱,如电子密度低所表明的那样。对于 c,c-CO 和 d,d-CO,零 K 下的位能面(potential energy surfaces)及其相关的、之前报道的室温自由能面都有所不同。