تفاعل #42652

معادلة التفاعل

t-butyl methyl ether hexane chloroform

(11β,16β)-9-fluoro-17-hydroxy-16-methyl-3,20-dioxo-11-[(trimethyl-silyl)oxy]-pregna-1,4-dien-21-yl acetate

ethyl isocyanate

→

title compound

المردود 62.5%

(11β,16β)-21-(acetyloxy)-9-fluoro-16-methyl-3,20-dioxo-11-[(trimethylsilyl)-oxy]pregna-1,4-dien-17-yl ethylcarbamate

المردود 62.5%

المذيبات

toluene

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةthe mixture was refluxed for 48 hours
2. 2
   أخرىevaporated under vacuum
3. 3
   أخرىto leave a slightly gummy solid

الإجراء التجريبي

To a mixture of (11β,16β)-9-fluoro-17-hydroxy-16-methyl-3,20-dioxo-11-[(trimethyl-silyl)oxy]-pregna-1,4-dien-21-yl acetate (3.11 g, 6.15 mmol) in 41 mL of toluene was added neat ethyl isocyanate (20.5 mL, 259 mmol) and the mixture was refluxed for 48 hours. The resulting solution was cooled to room temperature and evaporated under vacuum to leave a slightly gummy solid. Flash chromatography through a 1 kg column of silica gel eluting with t-butyl methyl ether/hexane/chloroform (1:1:1) gave 2.22 g of the title compound as a white solid.

المصدر