Methyl 4-nitro-5-[(E)-2-phenylethenyl]thiophene-2-carboxylate → methyl 5-phenyl-4H-thieno[3,2-b]pyrrole-2-carboxylate
Reaction equation
[N+:1]([C:4]1[CH:5]=[C:6]([C:17]([O:19][CH3:20])=[O:18])[S:7][C:8]=1/[CH:9]=[CH:10]/[C:11]1[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1)([O-])=O>P(OCC)(OCC)OCC>[C:11]1([C:10]2[NH:1][C:4]3[CH:5]=[C:6]([C:17]([O:19][CH3:20])=[O:18])[S:7][C:8]=3[CH:9]=2)[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1Participants
3
Reactant 1
Product 1
Reagents, catalysts & solvents 1
Procedure
A solution (1 M) of methyl 4-nitro-5-[(E)-2-phenylethenyl]thiophene-2-carboxylate in triethyl phosphite was heated to reflux for 28 h. After cooling down a part of the solvent was evaporated under high vacuum (2 mbar, water bath 60° C.) then the residue was purified by flash chromatography on silica gel (1:4 acetone/toluene) to afford the title compound (32%) as a solid.