| 摘要 |
<p>A method for catalytically reducing the carboxylic acid group of hydroxycarboxylic acids to a hydroxyl group is disclosed. An organic compound having an α-hydroxyl group and at least one carboxylic acid group is contacted with a catalyst in the presence of hydrogen to yield a reduced product having at least two hydroxyl groups, the carboxylic acid group having been converted into one of the hydroxyl groups. The catalytic process may be conducted at hydrogen pressures of less than about 50 atm and is particularly suited for converting α-hydroxycarboxylic acids, such as lactic acid or glycolic acid, to 1,2-dihydroxy alkanes, such as 1,2-propanediol or ethylene glycol, using zero valent copper. The catalyst may be supported on silica, and the hydroxyl groups on the silica may be capped with hydrophobic groups including alkyl groups and silanes, such as trialkylsilanes.</p> |
