3,3-Dimethyl-1,2,3,4-tetrahydroquinoxalin-2-one → 3,3-Dimethyl-4-[(1-methyl)ethyl]oxycarbonyl-1,2,3,4-tetrahydroquinoxalin-2-one

HRID 1378773Notes

Reaction equation

HRID 1378773 reaction equation
Cl[C:2]([N:4]1[C:13]2[C:8](=[CH:9][CH:10]=[CH:11][CH:12]=2)[NH:7][C:6](=[O:14])[C:5]1([CH3:16])[CH3:15])=[O:3].CC1(C)NC2C(=CC=CC=2)NC1=O.FC1C=C2C(=CC=1)NC(=O)C(C)(C)N2.[CH3:44][CH:45]([CH3:47])[O-:46].[Li+]>CC(O)C>[CH3:15][C:5]1([CH3:16])[N:4]([C:2]([O:46][CH:45]([CH3:47])[CH3:44])=[O:3])[C:13]2[C:8](=[CH:9][CH:10]=[CH:11][CH:12]=2)[NH:7][C:6]1=[O:14]

Participants

6

Reactant 4

HCID 5952033,3-Dimethyl-1,2,3,4-tetrahydroquinoxalin-2-oneHCID 229128184-Chlorocarbonyl-3,3-dimethyl-1,2,3,4-tetrahydroquinoxalin-2-oneHCID 229128926-Fluoro-3,3-dimethyl-3,4-dihydro-1H-quinoxalin-2-oneHCID 23673350Lithium propan-2-olate

Product 1

HCID 229128453,3-Dimethyl-4-[(1-methyl)ethyl]oxycarbonyl-1,2,3,4-tetrahydroquinoxalin-2-one

Reagents, catalysts & solvents 1

HCID 3776IsopropanolSolvent

Procedure

To 2.28 g of 4-chlorocarbonyl-3,3-dimethyl-1,2,3,4-tetrahydroquinoxalin-2-one (prepared by the method of Example 32 but using 3,3-dimethyl-1,2,3,4-tetrahydroquinoxalin-2-one rather than 6-fluoro-3,3-dimethyl-1,2,3,4-tetrahydroquinoxalin-2-one) in 25 ml of 2-propanol (the starting material is not all in solution) are added 0.694 g of lithium isopropoxide. After about 1.5 hr the reaction mixture became homogeneous and then again heterogeneous as the product precipitated out. After a total of 2 hr the solvent is removed under reduced pressure and the residue is partitioned between dichloromethane and saline. The organic layers are dried over sodium sulfate and the filtrate is concentrated. Ether is added and the resulting solid is collected to give the title compound, NMR (CDCl3) 1.28, 1.63, 5.01, 6.80, 6.98-7.11, 7.27, 7.96 δ.

Workup

  1. customagain heterogeneous as the product precipitated out
  2. customAfter a total of 2 hr the solvent is removed under reduced pressure
  3. customthe residue is partitioned between dichloromethane and saline
  4. dry with materialThe organic layers are dried over sodium sulfate
  5. concentrationthe filtrate is concentrated
  6. additionEther is added
  7. customthe resulting solid is collected

Sources & evidence

ORD record
ord-1bfd486817994e32ad19f42d8d0e179f
Source dataset
uspto-grants-1997_09
Patent number
US05668282

Reaction notes

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