29776-96-3Relevant academic research and scientific papers
Formation of C6H6 Isomers by Recombination of Propynyl in the System Sodium Vapour/Propynylhalide
Alkemade, U.,Homann, K. H.
, p. 19 - 34 (2007/10/02)
2-Propynyl radicals (C3H3) were generated from the respective chloride or bromide by the reaction Na + C3H3X -> C3H3 + NaX in a low-pressure flow reactor fed by multislit-diffusion burner.The temperature range was 623 to 673 K and total pressures of 300 and 600 Pa were applied.Analyses were performed by nozzle beam/mass spectrometry and by gas chromatography/mass spectrometry.The rate constants of the primary reactions were determined as k(Na + C3H3Cl) = 1.6E13 and k(Na + C3H3Br) = 7.8E13 cm3 mol-1 s-1, independent of temperature within the above range.The overall recombination rate constant of 2-propynyl was found to be 3.4E13 cm3 mol-1 s-1.The recombination products of propynyl were 1,5-hexadiyne, 1,2-hexadien-5-yne and 1,2,4,5-hexatetraene.Besides these direct products also 1,3-hexadien-5-yne and benzene were detected in relatively high yields which decreased with increasing pressure.A reaction mechanism via a propynyl-cyclopropene intermediate by which the chemically activated primary recombination products can rearrange to benzene and 1,3-hexadien-5-yne is discussed. - Keywords: Reaction kinetics / Hydrocarbon radicals / Sodium reactions / Benzene formation
