反应详情

温度

180 °C

A solution of the product from step b.) (10.9 g, 64 mmol) in decalin (193 ml) was treated with trimethylorthoacetate (48.2 ml, 384 mmol) and hexanoic acid (2.0 ml). Next, the reaction mixture was fitted with a Vigreaux column and heated to 180° C. for 18 hours. Additional hexanoic acid (3×1.5 ml) aliquots of hexanoic acid were added every 2 hours for the first 6 hours of reaction time. Next, the reaction was cooled to 22° C. and extracted with MeOH providing 27 g of a crude mixture of the diester and decalin. This mixture was dissolved in MeOH (250 ml), cooled to 0° C., and treated with 2 M NaOH (150 ml). After 12 hours, the solvent was evaporated and the residue was taken up in 2 N NaOH (100 ml) and washed with ether (2×150 ml). The basic layer was acidified with 4 M HCl to pH 1 and back extracted with EtOAc (4×100 ml). The organic layer was washed with brine, dried (MgSO4) and concentrated providing 6.4 g (54%) of the above subtitle compound.

1. customNext, the reaction mixture was fitted with a Vigreaux column
2. temperatureNext, the reaction was cooled to 22° C.
3. extractionextracted with MeOH providing 27 g of a crude
4. additionmixture of the diester and decalin
5. dissolutionThis mixture was dissolved in MeOH (250 ml)
6. temperaturecooled to 0° C.
7. additiontreated with 2 M NaOH (150 ml)
8. customthe solvent was evaporated
9. washwashed with ether (2×150 ml)
10. extractionback extracted with EtOAc (4×100 ml)
11. washThe organic layer was washed with brine
12. dry with materialdried (MgSO4)
13. concentrationconcentrated