反应详情

A solution of methyl 2-methoxy-3-(2-carbomethoxyethylthio)-3-[2-(8-phenyloctyl)phenyl]propanoate (0.5807 g, 1.2 mmoles) in methanol (5 ml) under argon was cooled to 0° C., after which 10% sodium hydroxide (1.5 ml, 3.5 mmoles) was added. The mixture was permitted to warm to room temperature and stirred for 2 hours. The methanol was evaporated and the mixture diluted with water. The pH of the aqueous layer was adjusted to 2 with dilute hydrochloric acid and extracted with ether. The organic phase was dried over magnesium sulfate, filtered and evaporated. The diastereomeric mixture of products was separated on a silica column using 23% ethyl acetate in hexane plus 0.5% formic acid. Five runs were made and the fractions analyzed on an analytical column. The separation provided both diastereomers in greater than 99% purity. The erythro isomer was obtained in 28% yield and the threo isomer in 22%. Erythro isomer: Analysis for C27H36SO5 1/8H2O:

1. customThe methanol was evaporated
2. additionthe mixture diluted with water
3. extractionextracted with ether
4. dry with materialThe organic phase was dried over magnesium sulfate
5. filtrationfiltered
6. customevaporated
7. additionThe diastereomeric mixture of products
8. customwas separated on a silica column
9. customThe separation
10. customprovided both diastereomers in greater than 99% purity
11. customThe erythro isomer was obtained in 28% yield