Water → (5,6-Dihydro-1,4,2-dioxazin-3-yl)-(2-hydroxy-phenyl)-methanone oxime

HRID 1858140Notes

Reaction equation

HRID 1858140 reaction equation
[O:1]1[CH2:6][CH2:5][O:4][C:3]([C:7]([C:9]2[CH:14]=[CH:13][CH:12]=[CH:11][C:10]=2[OH:15])=O)=[N:2]1.Cl.[NH2:17][OH:18].O>CN(C)C=O>[O:1]1[CH2:6][CH2:5][O:4][C:3]([C:7]([C:9]2[CH:14]=[CH:13][CH:12]=[CH:11][C:10]=2[OH:15])=[N:17][OH:18])=[N:2]1

Participants

5

Reactant 3

HCID 962WaterHCID 443297Hydroxyamine hydrochlorideHCID 11127466(5,6-Dihydro-1,4,2-dioxazin-3-yl)-(2-hydroxy-phenyl)-methanone

Product 1

HCID 136333718(5,6-Dihydro-1,4,2-dioxazin-3-yl)-(2-hydroxy-phenyl)-methanone oximeYield 60.8%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

At 80° C., 4.14 g (0.02 mol) of (5,6-dihydro-1,4,2-dioxazin-3-yl)-(2-hydroxy-phenyl)-methanone (III-1) in 20 ml of dimethylformamide are stirred with 2.1 g (0.03 mol) of hydroxylamine hydrochloride for 2 hours. The reaction mixture is poured into water and the resulting mixture is extracted with ethyl acetate, and the organic phase is dried over sodium sulphate and concentrated under reduced pressure. 4.7 g of crude product consisting of 15% E isomer and 57.5% Z isomer (HPLC) are obtained. The crude product is chromatographed over silica gel using a mixture of diethyl ether and petroleum ether (1:1). 2.7 g (60.8% of theory) of (5,6-dihydro-1,4,2-dioxazin-3-yl)-(2-hydroxy-phenyl)-methanone oxime (V-1) are obtained (content according to HPLC analysis: 93.4%).

Workup

  1. extractionthe resulting mixture is extracted with ethyl acetate
  2. dry with materialthe organic phase is dried over sodium sulphate
  3. concentrationconcentrated under reduced pressure
  4. customare obtained
  5. customThe crude product is chromatographed over silica gel using
  6. additiona mixture of diethyl ether and petroleum ether (1:1)

Sources & evidence

ORD record
ord-a4c4d776e1ec4076a0905708a562457e
Source dataset
uspto-grants-2000_11
Patent number
US06150521

Reaction notes

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