Consequences of rigidity and conformational locking in a 4,4-dimethyl-1,3-dioxolane ring system during protection of internal diol

The presence of an isopropylidene ketal protection of an internal diol in 3,4-O-isopropylidene-d-arabino-1-C-phenyl hexanone locks it in a conformation that prevents its cyclization to a pyranose ring.