Mechanistic studies of haloamination reactions promoted by metallic and organic catalysts

Abstract

This project aim to study chiral haloamination reactions aiming the synthesis of aminodiol. The allylic alcohol and, overall, its structural analogs are organic compounds that attract great attention from the scientific community, as they can be used as starting reactants for a series of target products. Here, we intend to evaluate new versions of chiral intramolecular haloamination reactions of allylic alcohol analogs promoted by Paladium(II)/Copper(II) and organocatalysts. To achieve this goal, we will use a coupled mass spectrometry/vibrational ion spectroscopy (IRMPD) approach supported by theoretical calculations to survey and to propose a catalytic cycle for the metallic and organic catalyzed haloamination reactions. We aim to identify by experimental techniques the reactive intermediates which support the proposed reaction mechanism. Therefore, by the proposition of catalytic cycles, we intend to achieve a better understanding on the origins of the regio-, diastero- and enantioselectivity on the haloaminated product formed.On the experimental side, the reactions will be monitored by ESI-MS and the reaction intermediates will be characterized by their mass to charge ratio, fragmentation pattern and their infrared vibrational IRMPD spectraOn the theoretical side, we aim to use electronic structure models to describe the kinetic and thermodynamic behavior of the proposed mechanism.Besides that, conformational search methods will be used to allow the assignment of the acquired IRMPD spectra.We believe that this project will allow the characterization of the protonation and coordination sites of several catalytic species and reactants used on the target synthesis as also as other widespread reactions.This proposal will foster the understanding of the catalytic cycle of this important class of reaction and, therefore, the development of new catalysts and reaction conditions with expressive enhancement of the reaction performance.