Hydroxyamine hydrochloride → 5-(Thiophen-2-YL)-1,2-oxazole

HRID 1264658Notes

Reaction equation

HRID 1264658 reaction equation
CN(C)[C:3](=[CH2:11])[C:4]([C:6]1[S:7][CH:8]=[CH:9][CH:10]=1)=[O:5].Cl.[NH2:14]O>CO>[S:7]1[CH:8]=[CH:9][CH:10]=[C:6]1[C:4]1[O:5][N:14]=[CH:11][CH:3]=1

Participants

4

Reactant 2

HCID 443297Hydroxyamine hydrochlorideHCID 22288452beta-Dimethylamino-1-(2-thienyl)-2-propen-1-one

Product 1

HCID 120499865-(Thiophen-2-YL)-1,2-oxazoleYield 93.3%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

A mixture of Compound 3 (18.1 g, 100 mmol) and hydroxylamine hydrochloride (7.0 g, 101 mmol) in 100 mL of anhydrous methanol was refluxed under nitrogen for 2 hours. The reaction mixture was cooled, concentrated and partitioned between water and dichloromethane. The dichloromethane layer was dried with anhydrous sodium sulfate, filtered and concentrated as to yield compound 4 as a dark yellow-orange oil (14.1 g, 93.3 mmol, 93%). GC/MS, m/z=151 at tR=8.30 min (100%). LC/MS,[M+H]=152.

Workup

  1. temperaturewas refluxed under nitrogen for 2 hours
  2. temperatureThe reaction mixture was cooled
  3. concentrationconcentrated
  4. custompartitioned between water and dichloromethane
  5. dry with materialThe dichloromethane layer was dried with anhydrous sodium sulfate
  6. filtrationfiltered
  7. concentrationconcentrated as

Sources & evidence

ORD record
ord-58f76ba247034a5cb9aea81f898637b5
Source dataset
uspto-grants-2003_04
Patent number
US06544999B2

Reaction notes

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