反应详情

The compound of formula 3 wherein W is a hydroxyl group may be prepared from the corresponding amine compound of formula 3, W is --NHR4 and R4 is hydrogen. One equivalent of α-amino(2,3-dihydro-5-benzofuranyl)acetic acid in a suitable acid such as hydrochloric, hydrobromic, sulfuric, phosphoric or acetic acid is reacted with 1 to 3 equivalents of an alkali metal nitrite such as sodium nitrite or potassium nitrite at a temperature of from 30° to 70° C. for from 2 to 8 hours to give the desired α-hydroxy(2,3-dihydro-5-benzofuranyl)acetic acid.