Ethyl bromoacetate → ethyl 2-(1-oxo-6-vinylphthalazin-2(1H)-yl)acetate

HRID 587233Notes

Reaction equation

HRID 587233 reaction equation
C(O[N:5]1[N:14]=[CH:13][C:12]2[C:7](=[CH:8][CH:9]=[C:10]([CH:15]=[CH2:16])[CH:11]=2)[C:6]1=[O:17])(=O)C.C(C1C=C2C(=CC=1)C(=O)NN=C2)=C.C([O-])([O-])=O.[Cs+].[Cs+].Br[CH2:38][C:39]([O:41][CH2:42][CH3:43])=[O:40]>CN(C=O)C>[O:17]=[C:6]1[C:7]2[C:12](=[CH:11][C:10]([CH:15]=[CH2:16])=[CH:9][CH:8]=2)[CH:13]=[N:14][N:5]1[CH2:38][C:39]([O:41][CH2:42][CH3:43])=[O:40]

Participants

6

Reactant 4

HCID 7748Ethyl bromoacetateHCID 10796Cesium carbonateHCID 866751746-vinylphthalazine-1(2H)-oneHCID 1317344121-oxo-6-vinylphthalazine-2(1H)-yl acetate

Product 1

HCID 86675173ethyl 2-(1-oxo-6-vinylphthalazin-2(1H)-yl)acetateYield 45%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

Ethyl-2-(1-oxo-6-vinylphthalazine-2(1H)-yl acetate (BI24): To a stirred solution of 6-vinylphthalazine-1(2H)-one (0.5 g, 2.90 mmol) in DMF (5.0 mL) was added Cs2CO3 (0.94 g, 2.90 mmol) and the reaction was stirred for 10 min Ethyl bromoacetate (0.48 g, 2.90 mmol) was added to the reaction mixture at ambient temperature and the reaction was stirred for 8 h at ambient temperature. The reaction mixture was diluted and extracted with EtOAc, and the EtOAc layer was washed with water and brine solution (2×). The separated EtOAc layer was dried over anhydrous Na2SO4 and concentrated under reduced pressure to afford crude product. The crude compound was purified by column chromatography (SiO2, 100-200 mesh; 25% EtOAc/petroleum ether) to afford the title compound as a brown solid (0.34 g, 45%): 1H NMR (400 MHz, DMSO-d6) δ 8.45 (m, 1H), 8.24 (m, 1H), 8.04 (m, 2H), 7.01 (m, 1H), 6.17 (d, J=2.1 Hz, 1H), 5.56 (d, J=10.8 Hz, 1H), 4.92 (s, 2H), 4.19 (m, 2H), 1.23 (m, 3H). ESIMS m/z 259.10 ([M+H]+); IR (thin film) 1750, 1660 cm−1.

Workup

  1. additionwas added to the reaction mixture at ambient temperature
  2. additionThe reaction mixture was diluted
  3. extractionextracted with EtOAc
  4. washthe EtOAc layer was washed with water and brine solution (2×)
  5. dry with materialThe separated EtOAc layer was dried over anhydrous Na2SO4
  6. concentrationconcentrated under reduced pressure
  7. customto afford crude product
  8. customThe crude compound was purified by column chromatography (SiO2, 100-200 mesh; 25% EtOAc/petroleum ether)

Sources & evidence

ORD record
ord-8b6b96daf22d474f85e8cabd6b5b5cae
Source dataset
uspto-grants-2016_01
Patent number
US09226500B2

Reaction notes

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