The product distribution obtained from the TiCl₄ initiated intramolecular isomerisations of 4-(methoxyphenyl and trimethoxyphenyl) dioxolanes at -78°C, -30°C and 0°C provided insights into the important regiochemical role played by these groups in such Mukaiyama type rearrangements through their resonance effects on the aryl ring of the dioxolanes.