Method B: R1R2C0+ R1RzCC12-R1R2C (OCHa) 2 acetals (Table I) were found to be free of ketones, as shoxm by the absence of infrared absorption in the carbonyl band, except for 5 and 8 which nonetheless gave satisfactory yields of dioxolanes. The vicinal glycol was obtained by hydrogenating (2-pyridyl)-1, 2-ethanediol hydrochloride12 (I) in water, acetic acid, or methanol using platinum oxide catalyst to give (2-piperidyl)-1, 2-ethanediol ...