STUDY OF INITIAL-STATE AND TRANSITION-STATE SOLVATION IN THE SOLVOLYSIS OF TERT-BUTYL HALIDES IN ALCOHOLS FROM INFINITE DILUTION ACTIVITY-COEFFICIENTS

• Tipo: Artigo em Revista Científica Internacional
• Data: 1993

Autores

GONCALVES, RMC (Autor) Outra; SIMOES, AMN (Autor) Outra; ALBUQUERQUE, LMPC (Autor) Outra; Maria Eugénia Macedo (Autor) FEUP

Revista

Título: Journal of Physical Organic Chemistry

Vol. 6

Páginas: 133-138

ISSN: 0894-3230

Editora: Wiley-Blackwell

Indexação

ISI Web of Knowledge - 8 Citações

Outras Informações

ID Authenticus: P-001-NAP

DOI: 10.1002/poc.610060302

Abstract (EN): The Gibbs energies of activation of the solvolytic reactions of tert-butyl halides (chloride, bromide and iodide) in eight mono-alcohols and eight di-alcohols were dissected into contributions from the initial state and transition state. The unified approach proposed by Abraham was applied and the various factors making up the overall solvent effect in both states were identified and compared. To perform this study, the Gibbs energies of transfer of the initial state were calculated using the infinite dilution activity coefficient values of the solutes in the solvents, gamma(infinity). These values were determined from the UNIFAC group-contribution method, with the modified Flory-Huggins equation in the combinatorial term and with group interaction parameters from the Parameter Table exclusively based on experimental gamma(infinity) data reported in the literature. It is concluded that solvent polarizability and polarity-HBD acidity and cavity effects during the activated process are mainly due to transition-state contributions.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 6