Ozonolysis of polycyclic aromatic hydrocarbons in participating solvents

Abstract

Seven polycyclic aromatic hydrocarbon (PAH) compounds that can be considered small models for graphene edges have been treated with ozone in solution. The presence of participating solvents such as water or methanol had a pronounced influence on conversion and identity of the functional groups formed, whereas the regioselectivity of the ozonation remained unaffected. Six previously unreported compounds have been isolated from the ozonolysis of pyrene 1, perylene 2 and benzo[e]pyrene 4.Comparison of the experimental data with calculated local ionization energy surfaces (IES) shows a good correlation, and indicates that this computational tool would be useful to predict the regioselectivity of ozone also for larger PAHs, including graphene and graphene nanoribbons.Chart 1 Pyrene (1), perylene (2), benzo[a]pyrene (B[a]P, 3), benzo[e] pyrene (B[e]P, 4), triphenylene (5), acenaphthylene (6) and anthracene (7). View Article Onlinea The 0.01 mmol scale experiments were performed by dissolving 0.01 mmol PAH in 2 mL DCM-d 2 , followed by ozone treatment and leaving the sample for 30 min at 20 C, then half the sample was transferred to a NMR tube and 1,2-DCE was added and half was treated with as much ozone again before it too was transferred to a NMR tube and 1,2-DCE added. b No new peaks in the 1 H NMR spectrum.This journal is

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