反应详情

To a solution of 11.0 g. of diisopropylamine in 50 ml. of anhydrous tetrahydrofuran at 0° was added 50 ml. of 2N butyllithium solution. To the resultant solution of lithium diisopropylamide was added a solution of 3.54 g. of (R)-6-benzyloxy-2,5,7,8-tetramethylchroman-2-acetic acid in 25 ml. of tetrahydrofuran. The resulting mixture was heated at 50° for 4 hours, acidified with 2N HCl and extracted with ether. The ether solutions were washed with brine, dried (Na2SO4) and stripped of solvent to give (±)-6-benzyloxy-2,5,7,8-tetramethylchroman-2-acetic acid, [α]D25 =±0°, m.p. 130°-133° .

1. temperatureThe resulting mixture was heated at 50° for 4 hours
2. extractionextracted with ether
3. washThe ether solutions were washed with brine
4. dry with materialdried (Na2SO4)