تفاعل #2045116

معادلة التفاعل

H2O

p-Toluenesulfonic acid

3,4-dihydro-2H-pyrane

methyl 3α,7α-dihydroxy-5β-cholan-24-oate

→

pure compound 2

المردود 90.0%

Methyl 3α,7α-ditetrahydropyranyloxy-5β-cholan-24-oate

المردود 90.0%

المذيبات

dioxane

ظروف التفاعل

المعالجة

1. 1
   تركيزthe mixture was partially concentrated under vacuum
2. 2
   استخلاصextracted with EtOAc (3×50 mL)
3. 3
   غسيلThe combined organic fractions were washed with brine (1×50 mL)
4. 4
   تجفيفdried (Na2SO4)
5. 5
   أخرىevaporated under vacuum
6. 6
   أخرىThe residue was purified by chromatography on silica gel column
7. 7
   غسيلElution with light petroleum/ethyl acetate 80/20

الإجراء التجريبي

p-Toluenesulfonic acid (78 mg, 0.41 mmol), 3,4-dihydro-2H-pyrane (20.1 ml, 0.098 mol) were added to a solution of methyl 3α,7α-dihydroxy-5β-cholan-24-oate (1) (2.0 g, 4.9 mmol) in dioxane (6 mL). The reaction mixture was stirred at room temperature for 15 min. H2O (50 mL) was then added and the mixture was partially concentrated under vacuum and extracted with EtOAc (3×50 mL). The combined organic fractions were washed with brine (1×50 mL), dried (Na2SO4) and evaporated under vacuum. The residue was purified by chromatography on silica gel column. Elution with light petroleum/ethyl acetate 80/20 afforded 2.5 g of the pure compound 2 (90% yield).

المصدر