Intramolecular Interactions between a Group Bearing n-Electrons and a CH2-X Where X is an Electronegative Group

Article abstract of DOI:10.1246/bcsj.54.3064

Conformational eguilibrium of 9-(2-acyloxyethyl)-1,4-dimethoxytriptycenes in chloroform-d suggests that the stability of the +/- sc conformation increases as the electronegativity of the acyl group increases.The results together with other pertinent data are disscused from the stand point that there is an attractive interaction between the acyloxymethyl and the methoxyl groups in proximity.Reflecting its high ionization potential, the chloro group in 1-position showed no stabilization of the +/- sc conformation, although mass spectra and some chemical properties indicat e that there is an interaction between the chloro group and highly electronegative CH2X group.A possible correlation of these results with the incipient transition state for S_N2 reactions is suggested.