Chloroform → (+)-Acetic acid cis-4-(tetrahydro-pyran-2-yloxy)-cyclopent-2-enyl ester

HRID 2550

반응식

HRID 2550 반응식
[O:1]1[CH2:6][CH2:5][CH2:4][CH2:3][CH:2]1[O:7][C@@H:8]1[CH2:12][C@H:11]([OH:13])[CH:10]=[CH:9]1.C(N(CC)CC)C.[C:21](OC=C)(=[O:23])[CH3:22].C(Cl)(Cl)Cl>COC(C)(C)C>[O:1]1[CH2:6][CH2:5][CH2:4][CH2:3][CH:2]1[O:7][C@@H:8]1[CH2:12][C@H:11]([O:13][C:21](=[O:23])[CH3:22])[CH:10]=[CH:9]1

참가 물질

6

반응물 4

HCID 6212Chloroform2회HCID 7904Vinyl AcetateHCID 8471TriethylamineHCID 13623252cis-4-Tetrahydropyranyloxy 2-cyclopentenol2회

생성물 1

HCID 13623284(+)-Acetic acid cis-4-(tetrahydro-pyran-2-yloxy)-cyclopent-2-enyl ester수율 45%

시약·촉매·용매 1

HCID 15413tert-Butyl methyl ether용매

실험 절차

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.

후처리

  1. filtrationThe reaction is then filtered through diatomaceous earth
  2. concentrationthe filtrate is concentrated under vacuum
  3. customThe products are separated by chromatography on silica gel (10% to 20% ethyl acetate/hexane)

출처 및 근거

ORD 기록
ord-23a5242235f843fa9d331c47debf3305
출처 데이터셋
uspto-grants-1998_03
특허 번호
US05728899

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