Thermokinetic study of the inactivation reaction of 1-methyl phthalazinium ylids

Abstract

The present paper consists in a thermokinetic study on the dimerization reactions of 1-methylphthalazinium ylids with –NO2 (ylid 1) and respectively, –O–CH3 (ylid 2) substituents in the p position of the benzoyl radical bound to the ylidic carbanion. From experimental data, the reaction order and rate constants have been calculated. The reaction order n = 2 confirmed the ylids’ dimerization reactions, while the values of the rate constants, k2 = 3.093x10-2L/mol s and, respectively, 2.16 x10-1 L/mol s for the dimerization of ylids 1 and 2 made evident the higher reactivity of ylid 2 versus ylid 1. The same conclusion is also supported by the results of the thermodynamic study based on the chemical affinity of the two reactions, when Ao dim,1 < Aodim,2.

Keywords

• 1-methylphthalazinium ylids
• dimerization
• inactivation
• thermokinetics (reaction order
• rate constants
• chemical affinity