Methyl iodide → (RS,SR)-3-[1-benzenesulfonyl-1-(5-methyl-[1,3,4]oxadiazol-2-yl)-ethyl]-cyclopentanone

HRID 602771Notes

Reaction equation

HRID 602771 reaction equation
[C:1]1([S:7]([CH:10]([C:17]2[O:18][C:19]([CH3:22])=[N:20][N:21]=2)[CH:11]2[CH2:15][CH2:14][C:13](=[O:16])[CH2:12]2)(=[O:9])=[O:8])[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[H-].[Na+].[CH3:25]I>CN(C=O)C.[NH4+].[Cl-]>[C:1]1([S:7]([C:10]([CH:11]2[CH2:15][CH2:14][C:13](=[O:16])[CH2:12]2)([C:17]2[O:18][C:19]([CH3:22])=[N:20][N:21]=2)[CH3:25])(=[O:9])=[O:8])[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=1

Participants

6

Reactant 3

HCID 6328Methyl iodideHCID 24758Sodium hydrideHCID 672667403-[Benzenesulfonyl-(5-methyl-[1,3,4]oxadiazol-2-yl)-methyl]-cyclopentanone

Product 1

HCID 67267203(RS,SR)-3-[1-benzenesulfonyl-1-(5-methyl-[1,3,4]oxadiazol-2-yl)-ethyl]-cyclopentanoneYield 24.3%

Reagents, catalysts & solvents 2

HCID 6228DimethylformamideSolventHCID 25517Ammonium ChlorideSolvent

Procedure

375 mg (1.17 mmol) of 3-[benzenesulfonyl-(5-methyl-[1,3,4]oxadiazol-2-yl)-methyl]-cyclopentanone in 10 mL of DMF, were treated with 52 mg (1.29 mmol, 1.1 eq) of NaH (55% in oil) over 30 min. 300 mg (2.32 mmol, 1.8 eq) of methyliodide were added, and after 2 hours, the reaction mixture was diluted with saturated aqueous NH4Cl and extracted with EtOAc. The combined organic phases were dried over Na2SO4, filtered and evaporated. The resulting two diastereomers were separated by column chromatography on silica gel with EtOAc/heptane 1:2, yielding 95 mg (24%) of (RS,SR)-3-[1-benzenesulfonyl-1-(5-methyl-[1,3,4]oxadiazol-2-yl)-ethyl]-cyclopentanone as a white solid, MS: 335 (MH+) and 90 mg (23%) of (RR,SS)-3-[1-benzenesulfonyl-1-(5-methyl-[1,3,4]oxadiazol-2-yl)-ethyl]-cyclopentanone as a white solid, MS: 335 (MH+).

Workup

  1. extractionextracted with EtOAc
  2. dry with materialThe combined organic phases were dried over Na2SO4
  3. filtrationfiltered
  4. customevaporated
  5. customThe resulting two diastereomers were separated by column chromatography on silica gel with EtOAc/heptane 1:2

Sources & evidence

ORD record
ord-a291040ab6844211b78b5d69d15ae21b
Source dataset
uspto-grants-2011_03
Patent number
US07906546B2

Reaction notes

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