Sigmatropic Rearrangements of Deprotonated Allyl Phenylacetates in the Gas Phase

Article abstract of DOI:10.1021/jo00232a030

The ion C6H5C-HCO2CH2CH=CH2 undergoes competitive losses of C3H5OH and CO2 on collisional activation.The loss of C3H5OH proceeds through ion complex -(C6H5CH=C=O)> yielding C6H5C<*>CO^- and C3H5OH.This reaction occurs without prior ester equilibration C6H5C^-HC(O)O^*C3H5<=>C6H5C^-HC(O^*)OC3H5.The elimination of CO2 follows rearrangement C6H5C^-HCO2C3H5->C6H5(C3H5)CHCO2^-.The rearrangement occurs through both six- and four-center transition states with the six-center (Claisen) rearrangement predominating.