反应详情

DIOP (64.8 mg.) was added to a solution of DTDR (46 mg.) in benzene (9 ml.) under nitrogen and the mixture allowed to stand for 15 minutes. This complex was then added to a mixture, prepared by adding ethanol (16 ml.) followed by (-)-α-methylbenzylamine (24 mg.) in ethanol (2 ml.) to the product of Example 2 (0.5 g.), under hydrogen. The reaction mixture was stirred under hydrogen for 51/2 hours at room temperature and then kept under hydrogen overnight. The solution was concentrated under reduced pressure and the residue treated with ether and aqueous 10% potassium carbonate. The ether extract was treated with the potassium carbonate extract, which was then acidified. The oil which separated, solidified and was extracted with ether and the extract dried, filtered, evaporated and the product recrystallised from light petroleum (b.p. 60°-80° C.) to give 2-(2-fluoro-4-biphenylyl)propionic acid, m.p. 101°-103° C., having an optical rotation [α]D20 +35.5° C. representing 89% of the (+) isomer in the product.

1. additionThis complex was then added to a mixture
2. customprepared
3. waitkept under hydrogen overnight
4. concentrationThe solution was concentrated under reduced pressure
5. additionthe residue treated with ether and aqueous 10% potassium carbonate
6. extractionThe ether extract
7. additionwas treated with the potassium carbonate
8. extractionextract
9. customThe oil which separated
10. extractionwas extracted with ether
11. customthe extract dried
12. filtrationfiltered
13. customevaporated
14. customthe product recrystallised from light petroleum (b.p. 60°-80° C.)