Desonide delta 9 (11) analog synthesis

Yield:5541-37-7 92%

Reaction Conditions:

with perchloric acid at -5 - 5;Cooling with ice;

Steps:

4 Example 4: Preparation of Compound of Formula V

Under ice-cooling, 6.4 g (17.8 mmol) of the compound of Formula IV was dissolved in 160 mL of acetone, using 7.2 g (71.7 mmol) of perchloric acid as a catalyst.Control the reaction temperature at -5 ~ 5 °C, TLC monitoring reaction until the end of the reaction,Saturated sodium bicarbonate solution was added to neutralize the excess acid, extracted three times with 80 mL of chloroform, washed with saturated brine, and the organic layer was retained. The organic solvent was removed under reduced pressure and silica gel column chromatography yielded 6.5 g (16.4 mmol) of Compound V in 92% yield.

References:

CN107778345,2018,A Location in patent:Paragraph 0039; 0052; 0053; 0054