INVESTIGADORES
BARRETO Gaston Pablo
artículos
Título:
Secondary inverse isotopic effect: thermal decomposition reaction in ethanol solution of deuterated acetone cyclic diperoxide and acetone diperoxide
Autor/es:
KARINA NESPRÍAS; NORA EYLER; ADRIANA CAÑIZO; GASTÓN BARRETO
Revista:
QUÃMICA NOVA
Editorial:
SOC BRASILEIRA QUIMICA
Referencias:
Lugar: San Pablo; Año: 2017
ISSN:
0100-4042
Resumen:
The characterization by mass spectrometry and the kinetic study of the thermal decomposition reaction of deuterated acetone diperoxide (dACDP) and acetone diperoxide (ACDP) were carried out in ethanol solution in the 140-165 ºC temperature range. The kinetic behavior observed in both cases follows a pseudo first order kinetic law up to at least 86 % peroxide conversions. The reactivity of these compounds was compared at different temperatures observing that, under the established experimental conditions, dACDP decomposes ca. 1.2 times faster than ACDP. It can be postulated that both peroxides decompose a little more by the same mechanism with substituent effect. The presence of deuterated substituents probably affects the stability of the tetraoxacyclohexane ring favoring the O-O bond rupture and the formation of the reaction products. A secondary inverse kinetic isotope effect is observed (kH/kD 1) since the bond to isotopically substituted atom in the reactant is not broken in the rate-determining step of the reaction.