Displacement Dynamics of Fluorine Atoms Reacting with Allyl Bromide Molecules

Article abstract of DOI:10.1021/j100066a018

Reactive scattering of F atoms with C3H5Br molecules leading to Br atom displacement has been studied at an initial translational energy E ca. 40 kJ mol^-1 using a supersonic beam of F atoms seed in He buffer gas.The center-of-mass angular distribution of C3H5F scattering shows a broad peak in the forward direction with roughly constant relative intensity ca. 0.4 in the backward hemisphere.The product translational energy distribution peaks at a low fraction f^'_pk ca. 0.1 of the total available energy with a tail extending up to higher energy.The reaction dinamics involve a stripping mechanism whereby the F atom adds to the C=C double bond, forming either the secondary fluorobromopropyl radical which dissociates directly to form allyl fluoride reaction product by bonding to the terminal CH2 group or the primary fluorobromopropyl radical which may dissociate by ring closure to form fluorocyclopropane reaction product by bonding to the intermediate CH group.The suggested occurence of two reaction pathways is inferred from the absence of H atom or CH2Br radical displacement pathways since the mass spectrometer detector does not distinguish between the proposed reaction products.