Selenium Dioxide → 5-Methoxy-4-nitro-2-benzothiazolecarboxaldehyde
Reaction equation
[Se](=O)=[O:2].[CH3:4][O:5][C:6]1[CH:7]=[CH:8][C:9]2[S:13][C:12]([CH3:14])=[N:11][C:10]=2[C:15]=1[N+:16]([O-:18])=[O:17]>O1CCOCC1>[CH3:4][O:5][C:6]1[CH:7]=[CH:8][C:9]2[S:13][C:12]([CH:14]=[O:2])=[N:11][C:10]=2[C:15]=1[N+:16]([O-:18])=[O:17]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 80 °C
Procedure
12.8 g (0.115 mol; 6 equivalents) of selenium dioxide is added to 4.34 g (19.3 mmol) of 5-methoxy-2-methyl-4-nitro-1,3-benzothiazole in solution in 180 ml of anhydrous dioxane. The reaction mixture is stirred at 80° C. for 18 hours then the insoluble matter is filtered and the solvent is evaporated off under reduced pressure. The expected aldehyde is obtained in the form of a yellow oil and purified on a silica column (eluent:ethyl acetate/heptane:gradient of 30% to 70%). Melting point: 154-155° C.