Computational study of the chemistry of 3-phenylpropyl radicals.
نویسندگان
چکیده
Density functional theory (DFT) and G3-type (G3(MP2)-RAD) composite calculations were performed on a series of substituted 3-phenylpropyl radicals, to determine the relative importance of fragmentation and cyclization reactions in the chemistry of such species. Our studies indicate that cyclization is generally the more important of these reactions, with exceptions where fragmentation yields highly stabilized benzylic species. The energetic barriers for the cyclization reactions (enthalpies of activation) were found to be determined largely by the stability of the reactant radical and to a lesser but significant extent, by steric factors. Polarity effects in the transition state (modeled by SOMO-LUMO gaps of the products) appear to be less important. The data obtained indicated that the addition of benzyl radical to alkenes may be considered to be irreversible, but calculations for α-substituted styrenic systems indicate that reversibility of addition may become a factor in dilute polymerizing solutions for select systems.
منابع مشابه
Hammett correlations in the chemistry of 3-phenylpropyl radicals.
The energetics and kinetics of the reaction of variously substituted benzyl radicals with a model alkene were calculated at the G3(MP2)-RAD//B3-LYP/6-31G(d) level of theory to determine whether such reactions are amenable to Hammett analysis. The reactions were studied both in the gas phase and in toluene solution in the temperature range 298-353 K; calculations include 1D-hindered rotor correc...
متن کاملComputational Model of Reaction Mechanism of Alkyl Peroxy Radicals with Organic Compounds in the Presence and Absence of Oxygen
On the basis of experimental data a kinetic model for the heterogeneous interaction between alkylperoxyradicals and organic compounds in Langmuir- Hinshelwood approach at room temperature has been offered.The effect of oxygen on the kinetics of process in the presence, [O2]o = 1 x 1011 – 1.6 x 1012 molecules.cm-2, and absence of oxygen has been analyzed. Over time the chain degenerate branching...
متن کاملAn EPR Study of Heterogeneous Reaction of CH3O2 Radicals with Organic Compounds: Effect of Organic Compound and Surface Nature
The reaction of CH3O2 radicals with acetaldehyde on the solid surface of NH4NO3 has been studied in a flow capillary reactor at low pressure and room temperature. The experiments were performed using EPR spectrometer combined with the kinetic method of radicals freezing. Peroxy radicals revealed an oscillation complex behavior during the process regarding to the phenomenon of radicals multiplic...
متن کاملTheoretical study of reaction of trifluoromethyl radical with hydroxyl and hydrogen radicals
متن کامل
Effect of the 3- and 4-Methyl Groups on the Opioid Receptor Properties of N-Substituted trans-3,4-Dimethyl-4-(3-hydroxyphenyl)piperidines
N-substituted trans-3,4-dimethyl-4-(3-hydroxyphenyl)piperidines (2a,b) are opioid receptor antagonists where the antagonist properties are not due to the type of N-substituent. In order to gain a better understanding of the contribution that the 3- and 4-methyl groups make to the pure antagonist properties of 2a,b, we synthesized analogues of 2a,b that lacked the 4-methyl (5a,b), 3-methyl (6a,b...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- The journal of physical chemistry. A
دوره 115 11 شماره
صفحات -
تاریخ انتشار 2011