Kinetics of arenesulfonylation of glycine, D,L-α-alanine, and D,L-valine in water-organic media

Quantum-chemical modeling of the mechanism for reaction of arenesulfonyl chlorides with α-amino acids

“…We have carried out systematic kinetic studies of the reactions of a-amino acids with arenesulfonyl chlorides in aqueous organic media [4][5][6], but the mechanism of these reactions in water-containing solvents has not been exactly established to date. Arenesulfonylation of a-amino acids by acid chlorides of aromatic sulfonic acids is classified as a nucleophilic substitution reaction occurring at a tetracoordinated hexavalent sulfur atom.…”

“…The calculated values of the activation energies for the gas-phase reactions of leucine, isoleucine, and also glycine [9] with BSC were compared with the activation energies for glycine, leucine, and isoleucine with 3-NBSC in the solvent water/1,4-dioxane, obtained as a result of the kinetic experiment [4][5][6]. for the reactions of methionine and proline with 3-NBSC in an aqueous dioxane solvent.…”

“…3. Activation energies for reactions of glycine (I), leucine (II), and isoleucine (III) with 3-NBSC in the solvent water-dioxane [4][5][6] vs. the activation energies for reactions of the same amino acids with BSC in the gas phase, obtained by calculation.…”