Adolfo Cuesta, Sebastian; Cordova-Sintjago, Tania; Ramon Mora, Jose published the artcile< Sulfonylation of Five-Membered Aromatic Heterocycles Compounds through Nucleophilic Aromatic Substitution: Concerted or Stepwise Mechanism?>, Recommanded Product: Ethyl 5-bromothiophene-2-carboxylate, the main research area is heterocyclic compound sulfonylation nucleophilic aromatic substitution mechanism activation energy.
Heterocyclic sulfones are relevant in medicinal chem., drug design and organic synthesis, and the mechanism of sulfonylation of five-membered heterocycles is not clear. In this work, it is presented a computational study on the mechanism of sulfonylation of five-membered heterocycles compounds Concerted and stepwise mechanisms for the nucleophilic aromatic substitution (SNAr) involved in the reaction were examined Effect of the neighboring group (NG), heteroatom in the ring (HT), nucleophile (NU), and leaving group (LG) in fourteen reactions were examined Anal. of the intrinsic reaction coordinate, reaction force, natural bond orbital (NBO) charges and bond indexes give a reasonable insight about the mechanism for the reactions studied. Results revealed activation free energies ranging from 20.8 kcal/mol up to 38.6 kcal/mol. Reaction force anal. showed that structural changes in the reactant are the most important component associated with the energy of activation with more than 60% of the contribution. Most sulfonylation reactions in this study proceed through a concerted mechanism; only two occur though a stepwise-Meisenheimer-intermediate mechanism.
ChemistrySelect published new progress about Activation energy. 5751-83-7 belongs to class bromides-buliding-blocks, and the molecular formula is C7H7BrO2S, Recommanded Product: Ethyl 5-bromothiophene-2-carboxylate.
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary