Method of preparing ascorbic acid and intermediates specially adapted for use therein
申请人:PFIZER INC.
公开号:EP0000092A1
公开(公告)日:1978-12-20
The invention relates to a process for preparing ascorbic acid in which (a) gulono-, galactono-, idono- or talono-1,4- lactone is reacted with at least one hydroxyl-protecting reagent so as to protected the free hydroxyl groups in the 5-, 6-and either the 2- or 3- positions, or, reacting gulono- or idono-1,4-lactone with at least one hydroxyl-protecting reagent so as to protect the free hydroxyl groups in the 3-, 5- and optionally the 6- positions (b) oxidizing the free hydroxyl group at the 2- or 3- position to oxidize it to an oxo group and (c) hydrolyzing the compound formed in (b) to ascorbic acid. Certain novel intermediates useful in the above process are also covered.
Ascorbic acid is prepared from a 1,4-lactone selected from gulono-1,4-lactone, galactono-1,4-lactone, idono-1,4-lactone and talono-1,4-lactone by a process comprising protection of the hydroxyl groups of the lactone so as to form an intermediate having a free hydroxyl group at either, but not both, the 2- or 3-position, oxidizing this free hydroxyl group to a keto group and hydrolyzing the oxidized intermediate to remove the hydroxyl-protecting groups.