Hydrazinecarboxylic acid, ethyl ester → 7-bromo-8-phenyl-2,4-dihydro-1H-pyrido[2,3-b][1,2,4]triazolo[4,3-d][1,4]oxazin-1-one

HRID 1509319Notes

Reaction equation

HRID 1509319 reaction equation
[Br:1][C:2]1[C:3]([C:13]2[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=2)=[CH:4][C:5]2[NH:10][C:9](=S)[CH2:8][O:7][C:6]=2[N:12]=1.C([O:21][C:22]([NH:24][NH2:25])=O)C>CC1C=CC(C)=CC=1>[Br:1][C:2]1[C:3]([C:13]2[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=2)=[CH:4][C:5]2[N:10]3[C:22](=[O:21])[NH:24][N:25]=[C:9]3[CH2:8][O:7][C:6]=2[N:12]=1

Participants

4

Reactant 2

HCID 20064Hydrazinecarboxylic acid, ethyl esterHCID 866836666-bromo-7-phenyl-1H-pyrido[2,3-b][1,4]oxazine-2(3H)-thione

Product 1

HCID 866836757-bromo-8-phenyl-2,4-dihydro-1H-pyrido[2,3-b][1,2,4]triazolo[4,3-d][1,4]oxazin-1-oneYield 27.3%

Reagents, catalysts & solvents 1

HCID 7809P-XyleneSolvent

Conditions

Temperature
180 °C

Procedure

In a 10 ml microwave vial was 6-bromo-7-phenyl-1H-pyrido[2,3-b][1,4]oxazine-2(3H)-thione (1 g, 3.11 mmol) and ethylhydrazine carboxylate (1.2 g, 12.44 mmol) in p-xylene (10 ml) to give a yellow suspension. The reaction mixture was heated to 180° C. for 45 minutes under microwave conditions. The crude residue was concentrated under reduced pressure and purified by Biotage silica gel chromatography (gradient 0% to 100% ethyl acetate in n-hexane) to give the title compound (293 mg, 27%). LCMS (Method D) RT 1.069 min, M+1=346.

Workup

  1. customto give a yellow suspension
  2. concentrationThe crude residue was concentrated under reduced pressure
  3. custompurified by Biotage silica gel chromatography (gradient 0% to 100% ethyl acetate in n-hexane)

Sources & evidence

ORD record
ord-414a8ae0e38f48e4aa9115458f845e4c
Source dataset
uspto-grants-2015_12
Patent number
US09221838B2

Reaction notes

Loading…