Department of Chemistry, Indian Institute of Technology Jodhpur, Jodhpur, Rajasthan 342037, India.
J Phys Chem A. 2022 Oct 6;126(39):6927-6933. doi: 10.1021/acs.jpca.2c04950. Epub 2022 Sep 21.
Aminohydroxymethylene (HN-C̈-OH) is the simplest aminooxycarbene which is a heteroatom stabilized carbene. This highly reactive molecule was prepared in an Ar matrix in a recent experimental work. Unimolecular reactivity of this astrochemically important molecule was investigated and only fragmentations were identified contrary to the observations of both fragmentations and intramolecular rearrangements in other hydroxycarbenes. These rearrangement reactions form the corresponding imine and carbonyl compounds. In the present work, direct chemical dynamics simulations of unimolecular chemistry of aminohydroxymethylene were performed in the gas phase to study atomic level dissociation mechanisms. Classical trajectories were generated using potentials and gradients computed at the density functional B3LYP/6-31+G* level of electronic structure theory. Simulation results showed that intramolecular rearrangements accompany fragmentations during the unimolecular decay process of aminohydroxymethylene. However, the average lifetime of the intermediate isomers were found to be only few picoseconds which might not have been long enough for detection in the experiments.
氨羟亚甲基（HN-C̈-OH）是最简单的氨氧基卡宾，它是一种杂原子稳定的卡宾。这种高反应性的分子在最近的一项实验工作中在 Ar 基质中制备。研究了这种天化学上重要的分子的单分子反应性，与其他羟卡宾中观察到的碎裂和分子内重排相反，只鉴定出了碎裂。这些重排反应形成相应的亚胺和羰基化合物。在本工作中，在气相中进行了氨羟亚甲基的单分子化学的直接化学动力学模拟，以研究原子水平的离解机制。使用在电子结构理论的密度泛函 B3LYP/6-31+G*水平计算的势能和梯度生成经典轨迹。模拟结果表明，在氨羟亚甲基的单分子衰变过程中，分子内重排伴随着碎裂。然而，中间体异构体的平均寿命仅为数皮秒，在实验中可能不够长，无法检测到。
