Ethanol → ethyl 2,2-bisfluoromethyl-6-nitro-2H-1-benzopyran-4-carboxylate
Reaction equation
[F:1][CH2:2][C:3]1([CH2:19][F:20])[CH:8]=[C:7]([C:9]([OH:11])=[O:10])[C:6]2[CH:12]=[C:13]([N+:16]([O-:18])=[O:17])[CH:14]=[CH:15][C:5]=2[O:4]1.S(=O)(=O)(O)O.[CH2:26](O)[CH3:27]>>[F:20][CH2:19][C:3]1([CH2:2][F:1])[CH:8]=[C:7]([C:9]([O:11][CH2:26][CH3:27])=[O:10])[C:6]2[CH:12]=[C:13]([N+:16]([O-:18])=[O:17])[CH:14]=[CH:15][C:5]=2[O:4]1Participants
4
Procedure
A mixture of 41.7 of 2,2-bisfluoromethyl-6-nitro-2H-1-benzopyran-4-carboxylic acid, 20 ml of sulfuric acid and 300 ml of ethyl alcohol was heated under refluxing for 6 hours. The reaction mixture was poured into ice-water, and the precipitated crystals were separated by filtration to obtain 42.7 g of ethyl 2,2-bisfluoromethyl-6-nitro-2H-1-benzopyran-4-carboxylate having a melting point of 96°-98° C.