Phosphorus oxychloride → Tert-butyl 4-[({4-[4-(3-bromo-4-fluorophenyl)-5-oxo-4,5-dihydro-1,2,4-oxadiazol-3-yl]-1,2,5-oxadiazol-3-yl}amino)carbonyl]-4-phenylpiperidine-1-carboxylate

HRID 82727

Reaction equation

HRID 82727 reaction equation
[NH2:1][C:2]1[C:3]([C:7]2[N:11]([C:12]3[CH:17]=[CH:16][C:15]([F:18])=[C:14]([Br:19])[CH:13]=3)[C:10](=[O:20])[O:9][N:8]=2)=[N:4][O:5][N:6]=1.[C:21]([O:25][C:26]([N:28]1[CH2:33][CH2:32][C:31]([C:37]2[CH:42]=[CH:41][CH:40]=[CH:39][CH:38]=2)([C:34](O)=[O:35])[CH2:30][CH2:29]1)=[O:27])([CH3:24])([CH3:23])[CH3:22].P(Cl)(Cl)(Cl)=O>CN(C)C1C=CN=CC=1.C(#N)C>[Br:19][C:14]1[CH:13]=[C:12]([N:11]2[C:10](=[O:20])[O:9][N:8]=[C:7]2[C:3]2[C:2]([NH:1][C:34]([C:31]3([C:37]4[CH:38]=[CH:39][CH:40]=[CH:41][CH:42]=4)[CH2:32][CH2:33][N:28]([C:26]([O:25][C:21]([CH3:24])([CH3:23])[CH3:22])=[O:27])[CH2:29][CH2:30]3)=[O:35])=[N:6][O:5][N:4]=2)[CH:17]=[CH:16][C:15]=1[F:18]

Participants

6

Conditions

Temperature
100 °C

Procedure

A solution of 3-(4-amino-1,2,5-oxadiazol-3-yl)-4-(3-bromo-4-fluorophenyl)-1,2,4-oxadiazol-5(4H)-one (0.15 g, 0.44 mmol), 1-(tert-butoxycarbonyl)-4-phenylpiperidine-4-carboxylic acid (0.4 g, 1.3 mmol), and 4-dimethylaminopyridine (32 mg, 0.26 mmol) in acetonitrile (2 mL) was treated with phosphoryl chloride (0.13 mL, 1.4 mmol) and heated in the microwave at 100° C. for 10 min. The reaction mixture was concentrated and the residue was diluted with ethyl acetate (25 mL) and washed with water (25 mL) and brine (25 mL), dried with sodium sulfate, filtered, and concentrated to a crude residue which was purified by silica gel to give the coupled product, tert-butyl 4-[({4-[4-(3-bromo-4-fluorophenyl)-5-oxo-4,5-dihydro-1,2,4-oxadiazol-3-yl]-1,2,5-oxadiazol-3-yl}amino)carbonyl]-4-phenylpiperidine-1-carboxylate. This material was diluted with dichloromethane (5 mL) and treated with 4.0 M HCl in 1,4-dioxane (3 mL) and stirred for 45 min. The reaction mixture was concentrated and the crude residue was purified by preparative LCMS to give the desired product (10 mg, 4%). LCMS for C22H19BrFN6O4 (M+H)+: m/z=529.0, 531.0.

Workup

  1. concentrationThe reaction mixture was concentrated
  2. additionthe residue was diluted with ethyl acetate (25 mL)
  3. washwashed with water (25 mL) and brine (25 mL)
  4. dry with materialdried with sodium sulfate
  5. filtrationfiltered
  6. concentrationconcentrated to a crude residue which
  7. customwas purified by silica gel

Sources & evidence

ORD record
ord-5960f277484f4295b2386e223e1ddadf
Source dataset
uspto-grants-2014_09
Patent number
US08846726B2

Linked notes

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