Homogeneous gas phase pyrolysis of N-t-butylacetamide

Abstract

The kinetics of the gas phase pyrolysis of N-t-butylacetamide have been studied in a static system over the temperature range 385–465°C. The decomposition occurs by two simultaneous, homogeneous and unimolecular processes. The major process (1) is the elimination of isobutene and the formation of acetamide; the minor process (2) is the elimination of t-butylamine and the formation of ketene. CH₃CONHC(CH₃)₃[graphic omitted](CH₃)₂CCH₂C + CH₃CONH₂(1), CH₃CONHC(CH₃)₃[graphic omitted](CH₃)₃CNH₂+ CH₂CO. (2) The rate constant for reaction (1) in the Arrhenius form is k₁= 10^12.42 exp (– 51 540/RT) s^–1(R in cal mol^–1 K^–1). The acetic acid formed by subsequent decomposition of the acetamide catalyses the formation of t-butylamine and the rate constant for this bimolecular process between 400–452°C is given by k₃= 10^13.56 exp (– 34 950/RT) cm³ mol^–1 s^–1. The transition state for reaction (1) is believed to be six-centred.