14N NMR Evidence for Initial Production of NH3 Accompanied by Alcohol from the Hydrolysis of Ethylamine and Butylamine in Supercritical Water

A 14N and 1H NMR spectroscopic study 1 was carried out to shed light on the microscopic aspects of the reaction of model alkylamines at a supercritical temperature of 400 °C. It is disclosed that NH3 and ROH (R = CH3CH2 and CH3 (CH2)3) are initially produced from the hydrolysis of ethylamine and butylamine, respectively. When the water density is doubled from 0.2 g cm−3, the pseudo-first-order reaction rate is markedly enhanced beyond the linear response. It suggests that the transition state of C-N bond cleavage is in a dipolar (ionic) state that can be more stabilized due to the many-body solvation by highly polar water molecules at a higher density.

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