Banca de QUALIFICAÇÃO: LUIS FELIPE DE RESENDE

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : LUIS FELIPE DE RESENDE
DATE: 29/04/2024
TIME: 15:30
LOCAL: REMOTO
TITLE:

NUCLEOPHILIC FLUORINATION WITH KF MEDIATED BY 18-CROWN-6: THEORETICAL INVESTIGATION OF THE EFFECT OF MICROSOLVATION ON SELECTIVITY

KEY WORDS:

Nucleophilic Fluorination, 18-crown-6 Ether, Microsolvation, Free Energy Diagram, Selectivity

PAGES: 28
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Físico-Química
SPECIALTY: Química Teórica
SUMMARY:

In the present study, we establish a fundamental basis for the mechanisms of SN2 and E2 reactions between primary and secondary bromides employing 18-crown-6 ether and KF, with the inclusion of the micro-solvation effect by t-ButOH and t-ButOHF3 in acetonitrile as the solvent. As a result, in addition to finding that SN2 products are favorable in all cases, we observe three main outcomes: i) The introduction of t-ButOH and t-ButOHF3 alcohols did not result in an increase in the solubility of KF, with the effect being more pronounced for the fluorinated compound; ii) Both alcohols contribute to an increase in the chemoselectivity for SN2 reactions, with this effect being more prominent for the primary substrate; and iii) Despite the increased chemoselectivity with the presence of alcohols, no increase in reactivity was observed through the reduction of the observable free energy barrier, indicating that a system remodeling is necessary. Consequently, all analyzed systems will be recalculated using the PCM solvation model with SES-type cavities for solvation free energy.

BANKING MEMBERS:
Externa à Instituição - ELOAH PEREIRA AVILA - UFJF
Externo ao Programa - 1712829 - LUIZ GUILHERME MACHADO DE MACEDO