5197-95-5Relevant articles and documents
Benzylic Ammonium Ylide Mediated Epoxidations
Roiser, Lukas,Robiette, Rapha?l,Waser, Mario
supporting information, p. 1963 - 1968 (2016/08/10)
A high yielding synthesis of stilbene oxides using ammonium ylides has been developed. It turned out that the amine leaving group plays a crucial role as trimethylamine gives higher yields than DABCO or quinuclidine. The amine group also influences the diastereoselectivity, and detailed DFT calculations to understand the key parameters of these reactions have been carried out.
EFFECTS OF SUBSTITUENTS IN THE BENZYL BROMIDE ON THE KINETICS OF THE BENZYLATION OF AMINES
Shpan'ko, I. V.,Korostylev, A. P.,Rusu, L. N.
, p. 1715 - 1723 (2007/10/02)
The kinetics of the reactions of 3- and 4-substituted benzyl bromides with amines having various structures in nitrobenzene at 40 deg C were investigated.The 4-substituted benzyl bromides have higher reactivity compared with that calculated on the basis of the linear correlations according to the Hammett-Taft equation for unsubstituted and 3-substituted benzyl bromides containing electron-withdrawning substituents.The reactivity of benzyl bromides containing electron-donating substituents obeys a linear correlation with the ?+ constants.The effects of structural changes in the substrate and the nucleophile on the character of the transition states of the investigated reactions is discussed.
α-Deuterium Isotope Effects in Benzyl Halides. 2. Reaction of Nucleophiles with Substituted Benzyl Bromides. Evidence for a Change in Transition-State Structure with Electron-Donating Substituents
Vitullo, V.P.,Grabowski, J.,Sridharan, S.
, p. 6463 - 6465 (2007/10/02)
Rates and α-D isotope effects have been determined for the following substrates and nucleophiles: p-methoxybenzyl bromide (Et3N, SCN-, N3-, OH-, S2O32-) benzyl bromide (Et3N, SCN-, N3-, OH-, S2O32-), and p-nitrobenzyl bromide (Et3N, SCN-, N3-, S2O32-).In nearly all cases the second-order rate constant for each nucleophile goes though a minimum for the unsubstituted compound while the α-D isotope increases monotonically in the sequence p-NO2>p-H>p-OCH3.These results are consistent with an increasing "looseness" of the SN2 transition state as the substituent on the aromatic ring becomes more electron donating.
