76160-35-5Relevant academic research and scientific papers
Enantioselective diamination with novel chiral hypervalent iodine catalysts
Mizar, Pushpak,Laverny, Aragorn,El-Sherbini, Mohammad,Farid, Umar,Brown, Michael,Malmedy, Florence,Wirth, Thomas
, p. 9910 - 9913 (2014/08/18)
Vicinal diamines constitute one the most important functional motif in organic chemistry because of its wide occurrence in a variety of biological and pharmaceutical molecules. We report an efficient metal-free, highly stereoselective intramolecular diamination using a novel chiral hypervalent iodine reagent together with its application as an efficient catalyst for the synthesis of diamines.
Kinetic Energy Release and Position of Transition State During the Intramolecular Substitution of Ionized 2-Benzoyl Pyridines
Schubert, Ralf,Gruetzmacher, Hans-Friedrich
, p. 122 - 130 (2007/10/02)
The loss of substituents X from molecular ions of ortho substituted 2-benzoyl pyridines has been investigated as a function of the dissociation energy of the C-X bond.Comparison of unimolecular and collisional induced decompositions of the resulting + ions and reference ions arising from 3-hydroxypyridoindole shows that cyclic fragment ions are formed in every case by an intramolecular substitution reaction with the exception of the parent compound (X=H), which gives rise to a mixture of + ions with different structures.The heat of formation of the cyclic ion has been estimated experimentally and by calculation using thermochemical data, and from this value and the appearance energies, the activation energies of the reverse reactions have been evaluated for the different reaction systems.Measurement of the kinetic energy release during the substitution reactions shows that only part of the reverse activation energy is released as kinetic energy.The energy partitioning quotient varies from 0.37 to 0.08 depending on the dissociation energy of the C-X bond or the reaction enthalpy.A sudden change in the energy partitioning quotient is observed with increasing exothermicity of the reaction, paralleling the behaviour of similar reaction systems.These results are interpreted as a demonstration of the influence of the variation of transition state position on the energy partitioning quotient.
