Sulfuric Acid → 4-Ethynyl-3-nitrosobenzamide

Reaction equation

[C:1]([C:3]1[CH:11]=[CH:10][C:6]([C:7]([NH2:9])=[O:8])=[CH:5][C:4]=1[NH2:12])#[CH:2].S(=O)(=O)(O)[OH:14].[Cr](O[Cr]([O-])(=O)=O)([O-])(=O)=O.[K+].[K+]>O>[C:1]([C:3]1[CH:11]=[CH:10][C:6]([C:7]([NH2:9])=[O:8])=[CH:5][C:4]=1[N:12]=[O:14])#[CH:2]

Participants

Procedure

0.46 g (2.87 mmol) 4-ethynyl-3-aminobenzamide (Compound XI-1), 10 ml water, were added into a 50 ml single-neck flask, then 1.2 g 58% sulfuric acid was added, and then 0.92 g 18.5% potassium dichromate solution. The mixture was stirred for 3 minutes until completing the reaction, extracted with ethyl acetate, dried over anhydrous sodium sulfate, and separated by column chromatography to obtain 0.06 g 4-ethynyl-3-nitrosobenzamide (Compound I-28, yellow-green solid), yield 12%, stored at −20° C.