Hydrogen exchange hydroxyl groups

The hydroxyl hydrogen exchanges but the hydrogen atoms of the CH3 (methyl) group do not. 

The oxidation of a hydroxyl group by an aluminum alkoxide-catalyzed hydrogen exchange with a receptor carbonyl compound is known as the Oppenauer oxidation. For oxidation of steroidal alcohols the reaction is generally... 

The trans elimination can take place if the basic sites of the alumina attack the hydrogen from one side of the plane and the hydroxyl group is removed from the opposite side of the plane by the acidic sites of the alumina. This may be possible if the reaction occurs within the pores of molecular dimensions (46) or within the crevices of the aluminas. Crevice sites on silica-alumina catalyst have been proposed by Burwell and co-workers (57) on the basis of racemization and exchange reactions of hydrocarbons. 

The component typically analyzed in plants is cellulose, which is the major structural carbohydrate in plants (Epstein et al. 1976, 1977). Cellulose contains 70% carbon-bound hydrogen, which is isotopically non-exchangeable and 30% of exchangeable hydrogen in the form of hydroxyl groups (Epstein et al. 1976 Yapp and Epstein 1982). The hydroxyl-hydrogen readily exchanges with the enviromnen-tal water and its D/H ratio is not a useful indicator of the D/H ratio of the water used by the plants. 

The surface of silica is highly reactive and hydroxyl groups exchange hydrogen for deuterium with D20 [14—16] but not with D2. They can be replaced by Cl from Cl2 or CC14 [16] and they react with silanes and aluminium chloride [15,19], Surface alcoholates are formed when silica is contacted with primary or secondary alcohols [20] either by the reaction with hydroxyl groups... 

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