Lithium diisopropylamide → HCID 69854211, compound

HRID 987914Notes

Reaction equation

HRID 987914 reaction equation
Br[CH2:2][C:3](=[CH2:14])[CH2:4][S:5]([C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1)(=[O:7])=[O:6].C([N-]C(C)C)(C)C.[Li+].[C:23]([O:27][C:28]([N:30]1[CH:34]([CH2:35][C:36]2[CH:41]=[CH:40][CH:39]=[CH:38][CH:37]=2)[CH:33]([CH2:42][CH:43]=[CH:44][C:45]([O:47][CH3:48])=[O:46])[O:32][C:31]1([CH3:50])[CH3:49])=[O:29])([CH3:26])([CH3:25])[CH3:24]>O1CCCC1>[C:23]([O:27][C:28]([N:30]1[CH:34]([CH2:35][C:36]2[CH:41]=[CH:40][CH:39]=[CH:38][CH:37]=2)[CH:33]([CH2:42][CH:43]2[CH:44]([C:45]([O:47][CH3:48])=[O:46])[CH2:14][C:3](=[CH2:2])[CH:4]2[S:5]([C:8]2[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=2)(=[O:6])=[O:7])[O:32][C:31]1([CH3:50])[CH3:49])=[O:29])([CH3:25])([CH3:26])[CH3:24]

Participants

5

Reactant 3

HCID 2724682Lithium diisopropylamideHCID 11022116Benzene, [[2-(bromomethyl)-2-propenyl]sulfonyl]-HCID 70034626HCID 70034626, compound

Product 1

HCID 69854211HCID 69854211, compound

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Conditions

Temperature
-78 °C

Procedure

A solution of (2-Bromomethyl-prop-2-ene-1-sulfonyl)-benzene (25.4 g, 92.5 mmol) in dry tetrahydrofuran (500 ml) was stirred at −78° C. under nitrogen during the addition of lithium diisopropyl amide (2M in hexanes, 46.3 ml, 92.5 mmol). The resulting mixture was stirred at −78° C. for 15 minutes and 4-Benzyl-5-(3-methoxycarbonyl-allyl)-2,2-dimethyl-oxazolidine-3-carboxylic acid tert-butyl ester (30 g, 77 mmol) in dry tetrahydrofuran (150 ml) then added via a cannula over 5 minutes. The resulting mixture was stirred at −78° C. for 2 hours, then quenched with saturated aqueous ammonium chloride solution and warmed to room temperature. After addition of brine and ethyl acetate, the phases were separated and the aqueous layer extracted with ethyl acetate. The combined organic layers were washed with brine, dried (anhydrous magnesium sulfate) and concentrated in vacuo to give, after purification by flash chromatography on silica gel (ethylacetate/hexane: 1/9 to 4/6) 5-(2-Benzenesulfonyl-5-methoxycarbonyl-3-methylene-cyclopentylmethyl)-4-benzyl-2,2-dimethyl-oxazolidine-3-carboxylic acid tert-butyl ester 41 g (89%) as a white foam. Mass spectrum 584 [M+H]+.

Workup

  1. stirringThe resulting mixture was stirred at −78° C. for 2 hours
  2. customquenched with saturated aqueous ammonium chloride solution
  3. temperaturewarmed to room temperature
  4. additionAfter addition of brine and ethyl acetate
  5. customthe phases were separated
  6. extractionthe aqueous layer extracted with ethyl acetate
  7. washThe combined organic layers were washed with brine
  8. dry with materialdried (anhydrous magnesium sulfate)
  9. concentrationconcentrated in vacuo
  10. customto give
  11. customafter purification by flash chromatography on silica gel (ethylacetate/hexane: 1/9 to 4/6) 5-(2-Benzenesulfonyl-5-methoxycarbonyl-3-methylene-cyclopentylmethyl)-4-benzyl-2,2-dimethyl-oxazolidine-3-carboxylic acid tert-butyl ester 41 g (89%) as a white foam

Sources & evidence

ORD record
ord-1f1723df9d4f472684334a3b35148313
Source dataset
uspto-grants-2003_10
Patent number
US06632826B1

Reaction notes

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