Ethanol → 2,2-dimethyl-5-(4-nitrophenyl)furan-3(2H)-one

Reaction equation

O[C:2]([CH3:17])([CH3:16])[C:3]#[C:4][C:5]([C:7]1[CH:12]=[CH:11][C:10]([N+:13]([O-:15])=[O:14])=[CH:9][CH:8]=1)=[O:6].C(NCC)C.C([OH:25])C>>[CH3:16][C:2]1([CH3:17])[C:3](=[O:25])[CH:4]=[C:5]([C:7]2[CH:12]=[CH:11][C:10]([N+:13]([O-:15])=[O:14])=[CH:9][CH:8]=2)[O:6]1

Participants

Reactant 3

HCID 702Ethanol2×

HCID 8021Diethylamine

HCID 593548124-Hydroxy-4-methyl-1-(4-nitrophenyl)pent-2-yn-1-one

Product 1

HCID 593547702,2-dimethyl-5-(4-nitrophenyl)furan-3(2H)-oneYield 92%

Procedure

To a stirred solution of 4-hydroxy-4-methyl-1-(4-nitrophenyl) pent-2-yn-1-one (1.74 g, 7.46 mmol, 1 eq) in ethanol (30 mL), a solution of diethylamine (778 mg, 7.46 mmol, 1 eq) in EtOH (5 mL) was added dropwise at RT. The reaction mixture was then stirred for additional 90 min. The ethanol was removed, and the mixture was then diluted with EtOAc (100 mL). The combined organic layers were washed with water (50 mL) and brine (20 mL), dried over Na2SO4, filtered, and concentrated in vacuo to afford 2,2-dimethyl-5-(4-nitrophenyl)furan-3(2H)-one (1.6 g, 92%) whichw as used in the next step without further purification.