| Abstract
| - An initial 1,2-hydrogen shift versus a 1,3-deuterium shift in emerging FCD2CH2CH2+ ions lead todiffering patterns of deuteration in the neutral products that are recovered following reaction with a Brønstedbase. Transient dideuterated fluoropropyl ions have been produced in [C3H4D2F+ PhO•] ion−neutral complexesby 70 eV electron impact on FCD2CH2CH2OPh and the resulting fluoropropenes collected in a specially designedelectron bombardment flow (EBFlow) reactor. Under these conditions ion−neutral complexes greatlypredominate over free fluoropropyl cations. Free ions afford products that are easily distinguished from thosethat result from ion−neutral complexes, in which the phenoxy radical serves as the Brønsted base. 1,2-Hydrogenshift yields ions containing CH3-groups, while the ions from 1,3-shift have CDH2-groups. Allyl fluoride and1-fluoropropene arise from ion−neutral complexes, and the extent and positions of deuteration have beendetermined by 19F NMR. Six deuterated variants of trans-1-fluoropropene can be resolved in the NMR spectrumof the neutral products collected from the EBFlow. The proportions of CH3 and CDH2 measured by integrationimply a branching ratio of 1,2-hydrogen versus 1,3-deuterium shift of approximately 94:6.
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