Gas-phase pyrolysis of 3,4-dihydro-2H-pyran

Abstract

The decomposition of 3,4-dihydro-2H-pyran between 316 and 389° has been found to be a first-order homogeneous process which yields equal amounts of acrolein and ethylene, as the only products. Addition of nitric oxide and increase of the surface–volume ratio of the reaction vessel had no effect upon the rate or the products of the decomposition. The results were treated by a rigorous least-squares computer program; each pressure and each time measurement were given individual weighting factors. On this basis the results over the pressure range 780–7466 N m^–2 could be represented by the expression k=(4·29 ± 0·09)× 10¹⁴ exp [(219,384 ± 96)/RT] s^–1 where R= 8·3144 J mol^–1 deg^–1