Diasteromeric effect on the homolysis of the C-ON bond in alkoxyamines: A DFT investigation of 1,3-Diphenylbutyl-TEMPO

Polymers

Volumn 2, Issue 3, 2010, Pages 353-363

  Blachon, Alexandra ^a   Marque, Sylvain R A ^a   Roubaud, Valérie ^a   Siri, Didier ^a  

^a AIX MARSEILLE UNIVERSITY   (France)

Author keywords

DFT calculations; Nitroxide mediated polymerization; Remote steric effect

Indexed keywords

ACTIVATION ENTROPIES; ALKOXYAMINES; ALKYL RADICALS; B3LYP/6-31G; DFT CALCULATION; DIASTEREOISOMERS; HOMOLYSIS; NITROXIDE MEDIATED POLYMERIZATION; REMOTE STERIC EFFECT; STERIC STRAINS;

ALKYLATION; POLYMERIZATION;

RATE CONSTANTS;

EID: 79952856345     PISSN: None     EISSN: 20734360     Source Type: Journal    
DOI: 10.3390/polym2030353     Document Type: Article

References (35)

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23. It is well known that geometry optimization performed by DFT with the B3LYP method provides geometries as reliable as those obtained with the ab initio MP2 methods. See: Koch, W.; Holthausen, M.C. A Chemist's Guide to DFT, 2nd ed.; Wiley-VCH: Weinheim, Germany, 2001; Chapter 8, pp. 119-136.
24. Calculations were started from conformations different from those displayed in Figures 1 and 2. In each case, conformations displayed in Figures 1 and 2 appeared as the most stable.
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29. TS involving large molecules and conformational changes are time-consuming and often difficult to determine, especially when the difference between TS is expected to be small. Thus, we preferred to discuss our results applying the Hammond postulate.
30. At first glance, it was not obvious that the phenyl group was bulkier than the methyl group because it is known as a Janus group whose size can be much smaller or much larger than that of the methyl group.
31. The conformation calculated for the enantiomer RR of 2 correspond to the conformation reported for the SS enantiomer of 7 [13]. It was assumed that the conformation given by the X-ray data was the most stable.
32. -1, Sobek, J.; Martschke, R.; Fischer, H. Entropy control of the cross-reaction between carbon-centered and nitroxide radicals. J. Am. Chem. Soc. 2001, 123, 2849-2857).
33. f.
34. 2.
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