Absolute rate constants for reactions of cumyloxy in solution

Abstract

H, m, ArH); MS (70 eV) m/e (relative intensity), 190 (M+ 100), 192 (34); UV (EtOH) 286 nm.3-Bromo-,16b 3-bromo-5-chloro-,16b 3-chloro-,l6b 3,5-dichloro-,16a 3-fluoro,31 and 5-chloro-3-fluorobenzofuran were prepared by dehydrohalogenation of 1, 3, 10, 12, 29, and 31, respectively, with i-BuOK in Z-BuOH. The 5-chloro-3-fluoro derivative showed the following spectroscopic characteristics: NMR (CC14) 7.20-7.50 (3 H, m, ArH), 7.48 (1 H, d, 37HF = 4.5 Hz, 2-H); MS (70 eV), m/e (relative intensity) 170 (M+, 100), 172 (35); UV (EtOH) 287, 294 nm.

Kinetic and chemical characterization of thermal decomposition of dicumylperoxide in cumene

“…The formation of the two main decomposition products, ACP and DMPC, was strictly related to the behaviour of these radicals. This species could undergo a ␤-scission (path 1 in Scheme 3) leading to the formation of ketone and a methyl radical or react with an H-donor to form carbinol (path 2) [11].…”

Kinetic modeling of the peroxide cross-linking of polymer/monomer blends: From a theoretical model framework to its application for a complex polymer/monomer dispersion system

“…Information about how the peroxide type affects the reactive bond is available from either experimental data or quantum chemistry calculations [27][28][29] and this effect on the rate constant had to be readily incorporated for various peroxides. The rate constants k ib,i,j,k were considered likewise [30][31][32], since these represent b-cleavage of oxy radical. Other constants essentially control the rates of peroxide, cross-linking, cross-link degradation and specific polymer chemistry.…”

“…Other constants essentially control the rates of peroxide, cross-linking, cross-link degradation and specific polymer chemistry. Using these considerations, a total of 10 rate constants (with k d,i,j,k,l,m,n and k ib,i,j,k , which could not have been obtained from literature [27][28][29][30][31][32]) for all potential substituents had to be determined, that is k iha,i,j,k,l,m,n , k iar,i,j,k,l,m,n,o , k it1,i,j,k,l,m,n , k it2,i,j,k,l,m,n , k ha,i,j,k,l,m,n , k ar,i,j,k,l,m,n,o , k t1,i,j,k,l,m,n , k t2,i,j,k,l,m,n , k b,i,j,k , and k e,i,j,k,l,m,n . The rate constants and the associated activation energies and pre-exponential factors were determined utilizing molecular modeling [22,23,33].…”

Autoxidation of phosphatidylcholines initiated with dicumylhyponitrite in solution and in bilayers

“…Although the cumyloxy radical (from DCHN) undergoes very rapid cleavage to acetophenone and methyl radical in aqueous solution (34), it is reported to have a higher reactivity in hydrogen abstraction than t -B~O (34,35). This current study reports on (1) An analysis of the l b decomposition products, a,a-dimethylbenzyl alcohol (DMBA), acetophenone (AP), and dicumylperoxide (DCP) in o-dichlorobenzene containing unsaturated phospholipids, and a comparison of the initiator efficiency, e, from these product data with the overall e measured by a phenolic inhibitor, a-tocopherol (a-T).…”