Benzyl Bromide → 3-Benzyl-5-[1-(4-nitrophenyl)-4-piperidyl]-2,3-dihydro-1,3,4-oxadiazol-2-one

HRID 515411Notes

Reaction equation

HRID 515411 reaction equation
[N+:1]([C:4]1[CH:9]=[CH:8][C:7]([N:10]2[CH2:15][CH2:14][CH:13]([C:16]3[O:20][C:19](=[O:21])[NH:18][N:17]=3)[CH2:12][CH2:11]2)=[CH:6][CH:5]=1)([O-:3])=[O:2].[C:22]1([CH2:28]Br)[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=1.C([O-])([O-])=O.[K+].[K+]>CN(C=O)C>[CH2:28]([N:18]1[N:17]=[C:16]([CH:13]2[CH2:14][CH2:15][N:10]([C:7]3[CH:6]=[CH:5][C:4]([N+:1]([O-:3])=[O:2])=[CH:9][CH:8]=3)[CH2:11][CH2:12]2)[O:20][C:19]1=[O:21])[C:22]1[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=1

Participants

5

Procedure

5-[1-(4-Nitrophenyl)-4-piperidyl]-2,3-dihydro-1,3,4-oxadiazol-2-one (5a 1.16 g, 4 mmol) on reacting with C6H5CH2Br (0.82 g, 4.8 mmol) in DMF in the presence of base K2CO3 (1.38 g, 10 mmol) at room temperature (27° C.) for 10 h, after completion of the reaction, reaction mixture is poured into ice water and extracted into chloroform finally purification by column chromatography to afford pure compound 3-benzyl-5-[1-(4-nitrophenyl)-4-piperidyl]-2,3-dihydro-1,3,4-oxadiazol-2-one (6c, 1.42 g, 94%). Nitro compound (6c, 1.52 g, 4 mmol) on reduction with SnCl2.2H2O (2.71 g, 12 mmol) in methanol and refluxed at 65° C. for 4 h, after completion of reaction methanol is evaporated under vacuum and to this saturated sodium bicarbonate solution is added to quench the excess stannous chloride and filtered through celite bed and purified in silica column (60-120) to afforded pure compound 5-[1-(4-aminophenyl)-4-piperidyl]-3-benzyl-2,3-dihydro-1,3,4-oxadiazol-2-one (7d, 1.23 g, 88%). To a stirred solution of 5-nitro2-furanoic acid in DMF add HOBT (Hydroxybenzotriazole) (0.14 g, 1 mmol), EDCI (1-Ethyl-3-(3-dimethylaminopropyl)carbodi imide)) (0.19 g, 1 mmol) and amine compound (7d, 0.35 g, 1 mmol) and stirred for 2 h at room temperature (27° C.), after completion of the reaction, reaction mixture is poured into ice water and extracted into chloroform finally purification by column chromatography using ethyl acetate-hexane (7:3) as eluant to afford pure compound N2-4-[4-(4-benzyl-5-oxo-4,5-dihydro-1,3,4-oxadiazol-2-yl)piperidino]phenyl-5-nitro-2-furamide (8d, 405 mg, 83%).

Workup

  1. custom(27° C.)
  2. customfor 10 h
  3. customafter completion of the reaction, reaction mixture
  4. extractionextracted into chloroform finally purification by column chromatography

Sources & evidence

ORD record
ord-99a52bce5f6042269ed3c8fdedbbe30c
Source dataset
uspto-grants-2015_08
Patent number
US09108960B2

Reaction notes

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