Dibromomethane → (S)-2-methyl-4-methylidene-3-(2-propynyl)-1-tert-butyldimethylsilyloxycyclopent-2-ene

HRID 1078997노트

반응식

HRID 1078997 반응식
BrCBr.O1CCC[CH2:5]1.[Si:9]([O:16][C@H:17]1[CH2:21][C:20](=O)[C:19]([CH2:23][C:24]#[CH:25])=[C:18]1[CH3:26])([C:12]([CH3:15])([CH3:14])[CH3:13])([CH3:11])[CH3:10].C(=O)(O)[O-].[Na+]>ClCCl.[Zn].[Ti](Cl)(Cl)(Cl)Cl.O.CCCCCC>[CH3:26][C:18]1[C@@H:17]([O:16][Si:9]([C:12]([CH3:15])([CH3:14])[CH3:13])([CH3:11])[CH3:10])[CH2:21][C:20](=[CH2:5])[C:19]=1[CH2:23][C:24]#[CH:25]

참가 물질

10

반응물 4

HCID 3024DibromomethaneHCID 8028Tetrahydrofuran2회HCID 516892Sodium BicarbonateHCID 11043662(S)-4-tert-butyldimethylsilyloxy-3-methyl-2-(2-propynyl)cyclopent-2-ene-1-one

생성물 1

HCID 11821434(S)-2-methyl-4-methylidene-3-(2-propynyl)-1-tert-butyldimethylsilyloxycyclopent-2-ene수율 68.7%

시약·촉매·용매 5

HCID 23994Zinc촉매HCID 24193Titanium Tetrachloride촉매HCID 962Water용매HCID 6344Dichloromethane용매2회HCID 8058Hexane용매

실험 절차

1H-NMR (solvent: CDCl3, internal standard: TMS) δ value (ppm): 4.69(brd, 1H), 3.11(ABq, 2H), 2.74(dd, 1H), 2.28(dd, 1H), 2.16(s, 3H), 1.96(t, 1H), 0.92(s, 9H), 0.15(s, 3H), 0.12(s, 3H). 2 Dibromomethane (13.04 g) and zinc dust (14.71 g) were added to tetrahydrofuran (120ml), and the resulting mixture was cooled to 0°~5° C. A dichloromethane solution (50 ml) of 1M titanium tetrachloride was added to the tetrahydrofuran solution over about 10 min, and the resulting mixture was allowed to react for 3 days at 0°~5° C. Then a solution of (S)-4-tert-butyldimethylsilyloxy-3-methyl-2-(2-propynyl)cyclopent-2-ene-1-one (13.22 g) in dichloromethane (50 ml) was added at 0°~5° C. over about 10 min. After the reaction was continued for 2 hours at the same temperature, hexane (200 ml) and then a slurry consisting of sodium bicarbonate (75 g) and water (40 ml) were added After stirring for 2 hours at 0°~5° C., the organic layer was separated by decantation. The obtained residue was extracted three times with n-hexane (200 ml). The combined organic layer was washed with saturated aqueous sodium bicarbonate solution, and dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure, and the resultant residue was subjected to silica gel column chromatography (eluent; n-hexane: ethyl acetate=50:1) to afford the desired product, (S)-2-methyl-4-methylidene-3-(2-propynyl)-1-tert-butyldimethylsilyloxycyclopent-2-ene (9.02 g, yield 68.7%) as a pale yellow oil.

후처리

  1. temperaturethe resulting mixture was cooled to 0°~5° C
  2. customto react for 3 days at 0°~5° C
  3. additionwere added
  4. customthe organic layer was separated by decantation
  5. extractionThe obtained residue was extracted three times with n-hexane (200 ml)
  6. washThe combined organic layer was washed with saturated aqueous sodium bicarbonate solution
  7. dry with materialdried over anhydrous sodium sulfate
  8. customThe solvent was evaporated under reduced pressure

출처 및 근거

ORD 기록
ord-5540c9f93f7045289ad831cc82e1ba82
출처 데이터셋
uspto-grants-1996_08
특허 번호
US05550260

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