Cyclopolymerization reactions of diallyl monomers: exploring electronic and steric effects using DFT reactivity indices.
The regioselectivity in the cyclopolymerization of diallyl monomers is investigated using DFT-based reactivity indices. In the first part, the experimentally observed mode of cyclization (exo versus endo) of 11 selected radicals involved in this process is reproduced by the computation of activation energies, entropies, enthalpies, and Gibb's free energies for the 5- and 6-membered cyclization reactions. The application of a recently proposed energy partitioning of the activation barriers shows that the regioselectivity cannot be explained by the steric effect alone. Next, a number of relevant DFT-based reactivity indices, such as non-spin-polarized and spin-polarized Fukui functions, spin densities, and dual descriptors, were applied to probe the role of the polar and stereoelectronic effects in this reaction. The dual descriptor has been found to reproduce best the experimental trends, confirming the important role of the stereoelectronic effects.
Uğur
Ilke
I
Chemistry Department, Faculty of Arts and Sciences, Boğaziçi University, 34342 Bebek, Istanbul, Turkey.
De Vleeschouwer
Freija
F
Tüzün
Nurcan
N
Aviyente
Viktorya
V
Geerlings
Paul
P
Liu
Shubin
S
Ayers
Paul W
PW
De Proft
Frank
F
D000498:Allyl Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D003198:Computer Simulation; D003500:Cyclization; D004583:Electrons; D008956:Models, Chemical; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism; D013816:Thermodynamics
D000498:Allyl Compounds; D011108:Polymers