Uncatalyzed and chorismate mutase-catalyzed Claisen rearrangements of 5,6-dihydrochorismate and 6-oxa-5,6-dihydrochorismate

The synthesis of 6-oxa-5,6-dihydrochorismic acid (4) from D-xylose is described. The half-lives for the uncatalyzed Claisen rearrangements of 5,6-dihydrochorismic acid (3) and 4 in D 2 O at 30 o C were 49 000 and 1200 h, respectively, compared to a half-life of 15.6 h for chorismic acid (I) under similar conditions