Banca de DEFESA: LUIS FELIPE DE RESENDE

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : LUIS FELIPE DE RESENDE
DATE: 02/08/2024
TIME: 14:00
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, including the effect of micro-solvation by t-ButOH, t-ButOHF3, and 2,3-dimethylbutane-2,3-diol in acetonitrile as solvent. As a result, in addition to the finding that SN2 products are favorable in all cases, we observed three main outcomes: i) The introduction of all alcohols t-ButOH, t-ButOHF3, and diol resulted in an increase in KF solubility, with the most pronounced effect for the diol, followed by the fluorinated alcohol; ii) Both alcohols contribute to an increase in chemoselectivity for SN2 reactions, with this effect being more notable for the primary substrate; and iii) Despite the greater chemoselectivity in the presence of the alcohols, no increase in reactivity was observed through the reduction of the observable free energy barrier for t-ButOH, but such an increase was observed for the fluorinated alcohol and diol.

BANKING MEMBERS:
Externa à Instituição - ELOAH PEREIRA AVILA - UFJF
Presidente - 1623600 - JOSEFREDO RODRIGUEZ PLIEGO JUNIOR
Externo ao Programa - 1712829 - LUIZ GUILHERME MACHADO DE MACEDO