6119-32-0Relevant articles and documents
Tris(trimethylsilyl)silane (TTMSS)-derived radical reactivity toward alkenes: A combined quantum mechanical and laser flash photolysis study
Lalevee, Jacques,Allonas, Xavier,Fouassier, Jean Pierre
, p. 6434 - 6439 (2007)
(Figure Presented) The reactivity of the tris(trimethylsilyl)silane (TTMSS)-derived radical is studied through an approach combining laser flash photolysis and quantum mechanical calculations. The results obtained for TTMSS are compared both to a classica
The effect of the medium polarity on the mechanism of the reaction of hydroxybenzenes with hydrazyl radical in aprotic solvents
Belaya,Belyj,Zarechnaya,Scherbakov,Mikhalchuk,Doroshkevich
, p. 690 - 697 (2017/05/29)
Mechanisms of the reaction of di- and trihydroxybenzenes with 2,2′-diphenyl-1-picrylhydrazyl (stable radical) in aprotic media of different polarity have been elucidated by experimental and quantum-chemical methods. Kinetic, stoichiometric, and activation
Structural and medium effects on the reactions of the cumyloxyl radical with intramolecular hydrogen bonded phenols. the interplay between hydrogen-bonding and acid-base interactions on the hydrogen atom transfer reactivity and selectivity
Salamone, Michela,Amorati, Riccardo,Menichetti, Stefano,Viglianisi, Caterina,Bietti, Massimo
supporting information, p. 6196 - 6205 (2014/07/21)
A time-resolved kinetic study on the reactions of the cumyloxyl radical (CumO?) with intramolecularly hydrogen bonded 2-(1-piperidinylmethyl)phenol (1) and 4-methoxy-2-(1-piperidinylmethyl)phenol (2) and with 4-methoxy-3-(1-piperidinylmethyl)phenol (3) has been carried out. In acetonitrile, intramolecular hydrogen bonding protects the phenolic O-H of 1 and 2 from attack by CumO? and hydrogen atom transfer (HAT) exclusively occurs from the C-H bonds that are α to the piperidine nitrogen (α-C-H bonds). With 3 HAT from both the phenolic O-H and the α-C-H bonds is observed. In the presence of TFA or Mg(ClO 4)2, protonation or Mg2+ complexation of the piperidine nitrogen removes the intramolecular hydrogen bond in 1 and 2 and strongly deactivates the α-C-H bonds of the three substrates. Under these conditions, HAT to CumO? exclusively occurs from the phenolic O-H group of 1-3. These results clearly show that in these systems the interplay between intramolecular hydrogen bonding and Br?nsted and Lewis acid-base interactions can drastically influence both the HAT reactivity and selectivity. The possible implications of these findings are discussed in the framework of the important role played by tyrosyl radicals in biological systems.