تفاعل #2646
ord-23a5242235f843fa9d331c47debf3305
معادلة التفاعل
المتفاعلات
الكواشف
المذيبات
ظروف التفاعل
المعالجة
- 1ترشيحThe reaction is then filtered through diatomaceous earth
- 2تركيزthe filtrate is concentrated under vacuum
- 3أخرىThe products are separated by chromatography on silica gel (10% to 20% ethyl acetate/hexane)
الإجراء التجريبي
Cis-4-(tetrahydro-pyran-2-yloxy)-cyclopent-2-enol (1.091 g, 5.92 mmol, prepared in example 6) is dissolved in tert-butyl methyl ether (8.6 mL, anhydrous). To the solution is added triethylamine (0.59 mL, 4.2 mmol), pancreatin (3.2 g, available from Sigma Chemical Company), and vinyl acetate (2.7 mL, 29 mmol). The reaction is allowed to stir for 7 hours at room temperature. The reaction is then filtered through diatomaceous earth and the filtrate is concentrated under vacuum. The products are separated by chromatography on silica gel (10% to 20% ethyl acetate/hexane) to provide (-)-acetic acid cis-4-(tetrahydro-pyran-2-yloxy)-cyclopent-2-enyl ester (B, 601 mg, 45% yield, 91% ee) [α]D =-19.8°,(c=1.00, chloroform) as a yellow oil and (-)-cis-4-(tetrahydro-pyran-2-yloxy)-cyclopent-2-enol (A, 560 mg, 50% yield, 94% ee), [α]D =-9.9°, (c=1.06, chloroform) as a yellow oil.