Sulfuric Acid → HCID 9841373, compound

HRID 1107266Notes

Reaction equation

HRID 1107266 reaction equation
[OH:1][CH:2]([C:9]1[N:13]=[C:12]([N:14]2[CH2:19][CH2:18][N:17]([C:20]3[CH:25]=[CH:24][CH:23]=[CH:22][N:21]=3)[CH2:16][CH2:15]2)[S:11][N:10]=1)[C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][CH:4]=1.S(=O)(=O)(O)O.[OH-].[Na+]>CC(C)=O.O.C(OCC)(=O)C.[O-2].[O-2].[O-2].[Cr+6]>[C:2]([C:9]1[N:13]=[C:12]([N:14]2[CH2:15][CH2:16][N:17]([C:20]3[CH:25]=[CH:24][CH:23]=[CH:22][N:21]=3)[CH2:18][CH2:19]2)[S:11][N:10]=1)(=[O:1])[C:3]1[CH:4]=[CH:5][CH:6]=[CH:7][CH:8]=1

Participants

8

Reactant 3

HCID 1118Sulfuric AcidHCID 14798Sodium HydroxideHCID 9928497HCID 9928497, compound

Product 1

HCID 9841373HCID 9841373, compoundYield 75.3%

Reagents, catalysts & solvents 4

HCID 10219390chromium (VI) trioxideCatalystHCID 180AcetoneSolventHCID 962WaterSolventHCID 8857Ethyl AcetateSolvent

Procedure

To an ice-cooled suspension of 3-(1-hydroxy- 1-phenylmethyl)-5-[1-(2-pyridyl)piperazin-4-yl]-1,2,4-thiadiazole (0.625 g, 1.77 mmol) in acetone was added dropwise over a period of ca. 10 min a solution of chromium trioxide (0.15 g, 1.5 mmol) dissolved in water (12 mL) and conc. sulfuric acid (0.33 mL). The resulting mixture was allowed to warm to room temperature and stirred for 16 h. The reaction mixture was diluted with ethyl acetate (100 mL), then made basic (pH ca. 10) by the addition of 3N sodium hydroxide solution. The organic layer was collected, washed with water, dried (sodium sulfate), filtered and concentrated in vacuo. Purification by column chromatography on silica gel using a solvent gradient of a mixture of hexane and ethyl acetate (6/4 and 4/6) afforded the title compound (390 mg, 75.3%) as a light yellow solid. The starting material (101 mg, 16.2%) was also recovered. M.p. 109.5-111.0° C.; 1H-NMR (CDCl3) δ8.23-8.26 (m, 3H), 7.50-7.63 (m, 4H), 6.73-6.74 (m, 2H), 3.79 (m, 8H, 4CH2); MS m/z 352 (M+ +1), 309, 258, 232, 204,147, 121,104, 77.

Workup

  1. customThe organic layer was collected
  2. washwashed with water
  3. dry with materialdried (sodium sulfate)
  4. filtrationfiltered
  5. concentrationconcentrated in vacuo
  6. customPurification by column chromatography on silica gel using
  7. additiona solvent gradient of a mixture of hexane and ethyl acetate (6/4 and 4/6)

Sources & evidence

ORD record
ord-fe84bc6d4ae242c0b4957793269f8534
Source dataset
uspto-grants-2000_05
Patent number
US06060472

Reaction notes

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