Effect of collision energy on the reaction mechanism of C(3P) + OH(X 2 Π) → CO(X 1 Σ +) + H(2S)

Abstract

Quasiclassical trajectory calculations based on a fully global ab initio potential energy surface of the rotational angular momentum polarisation of the product CO in the title reaction are reported. The alignment and orientation of the rotational angular momentum of the CO fragment in the scattering frame were found to be sensitive to the initial collision energy chosen. Differences in the angular momentum polarization at different collision energies were traced to differences in the microscopic reaction mechanism. The results of this study suggest that the title reaction is mainly dominated by an abstraction reaction mechanism (involving the short-lived and metastable intermediate complex COH) at low collision energies; however, at relatively high energies, an insertion reaction mechanism (involving the long-lived and stable intermediate complex HCO) plays a role.

Intriguing generative metabolism discovery of reactive metabolite nitroso of lapatinib and relevant structural modification

“…One presents a double bond at C 6 -N 7 , which has been discussed. [19] Another presents a double bond at C 8 , which is detected in the experiment, [10,17] with an energy barrier of 6.30 kcal/mol for HS pathway (Figure 2, Figure S1). While the transition state (TS) of the LS pathway is not found despite our many attempts, we can speculate the feasibility of the LS pathway based on similarity with nitrone forming a double bond at C 6 -N 7, [19] which is easier to achieve in the LS pathway than the HS pathway with a much lower energy barrier.…”

“…Based on metabolic characteristic of lapatinib, two metabolic directions of lapatinib, N-dealkylation, which has been studied before, [19] and N-hydroxylation, were designed to explore the production of nitroso (Scheme 1). Depending on the specific metabolic intermediates, the N-hydroxylation was further divided into two paths: paths A and B.…”

“…For comparison, we incorporated previous study, that the N-dealkylation pathway [19] (path C) can also form primary hydroxylation amine I-M 3 , into this study. The energy barrier of the determining step of path C is 16.56 kcal/mol ( Figure 2) with regard to the HAT process for I-M 2 to I-IM 3 .…”

“…The determining step of this process is dehydration with an energy barrier of 35.09 kcal/mol, which is hard to achieve. Our previous study [19] presented details of the primary amine from N-dealkylation lapatinib, which forms nitroso by dihydroxylation and further dehydration. The rate-determining step is also difficult to achieve with an energy barrier of 36.71 kcal/mol.…”

Electroosmotic pump‐supported molecularly imprinted monolithic column for capillary chromatographic separation of nitrophenol isomers

“…In our case, a MIP monolith was fabricated using 4-NP as template molecule, 4-VP as the functional monomer and EGDMA as cross-linker, respectively. The molar ratio of 4-NP/4-VP/EGDMA was set at 1:3:15 [25]. A series of MIP capillary columns were prepared according to the conditions shown in Table 1.…”