4-Methoxybenzenesulfonyl chloride → N-[4-methoxybenzenesulfonyl]-(D)-valine

HRID 264278Notes

Reaction equation

HRID 264278 reaction equation
[NH2:1][C@@H:2]([C:6]([OH:8])=[O:7])[CH:3]([CH3:5])[CH3:4].O1CCOCC1.O.C(N(CC)CC)C.[CH3:23][O:24][C:25]1[CH:30]=[CH:29][C:28]([S:31](Cl)(=[O:33])=[O:32])=[CH:27][CH:26]=1>C(Cl)Cl>[CH3:23][O:24][C:25]1[CH:26]=[CH:27][C:28]([S:31]([NH:1][C@@H:2]([C:6]([OH:8])=[O:7])[CH:3]([CH3:5])[CH3:4])(=[O:33])=[O:32])=[CH:29][CH:30]=1

Participants

6

Procedure

To a solution of D-valine (15.0 g, 128.0 mmol) in 1:1 dioxane/water (200 mL) containing triethylamine (19.4 g, 192.0 mmol) at room temperature is added 4-methoxybenzene-sulfonyl chloride (29.0 g, 141.0 mmol), and the reaction mixture is stirred at room temperature overnight. The mixture is then diluted with methylene chloride, washed with 1N aqueous hydrochloric acid and water. The organic layer is washed again with brine, dried (Na2SO4), and the solvent is evaporated to provide N-[4-methoxybenzenesulfonyl]-(D)-valine as a crude product. A solution of this crude product (15.0 g) in toluene (100 mL) containing N,N-dimethylformamide di-t-butyl acetal (50 mL, 206.5 mmol) is heated to 95° C. for 3 hours. The solvent is then evaporated. The crude product is purified by silica gel chromatography (30% ethyl acetate/hexanes) to provide N-[4-methoxybenzene-sulfonyl]-(D)-valine t-butyl ester.

Workup

  1. washwashed with 1N aqueous hydrochloric acid and water
  2. washThe organic layer is washed again with brine
  3. dry with materialdried (Na2SO4)
  4. customthe solvent is evaporated

Sources & evidence

ORD record
ord-94c9da312d5f43789f00688d9c9edd22
Source dataset
uspto-grants-1997_07
Patent number
US05646167

Reaction notes

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