Infrared Laser Induced Decomposition of Tetrahydrofuran

Article abstract of DOI:10.1021/j100390a007

The pulsed CO2 laser induced decomposition of tetrahydrofuran (THF) has been studied as a function of the THF pressure,focal length of lense, and added gases.The stable reaction products were analyzed by gaschromatography.Although C2H4 and C3H6 were the dominant hydrocarbon products under all experimental conditions, the distribution of C2H4 and C3H6, as well as lesser products, was shown to be very independent upon the experimantal conditions.The laser induced reaction, studied in the pressure range 0.1-12 torr of THF, exhibited two different pressure regimes above and below ca. 2 torr of THF.We propose a mechanism involving breakage of the CO bond in THF to form an unstable 1,5 diradical which further decomposes via two different pathways.Each channel splits out a stable molecule and another diradical.One of the diradicals isomerizes and decomposes to radicals, while the other diradical closes or rearranges and is predominantly stabilized.Under the conditions of low THF pressure and a short focal length lens, the radicals produced react principally via radical-radical reactions.At higher THF pressures radical-THF reactions strongly perturb the product distribution.Evidence for collisional energy pooling reactions and rotational hole filling is presented.