3-Thiophenecarboxylic acid, tetrahydro-4-oxo-, methyl ester → HCID 12953041, compound
Reaction equation
[NH2:1][C:2]1[CH:12]=[CH:11][C:5]([C:6]([O:8][CH2:9][CH3:10])=[O:7])=[CH:4][N:3]=1.O=[C:14]1[CH2:18][S:17][CH2:16][CH:15]1[C:19](OC)=[O:20].O.C1(C)C=CC(S(O)(=O)=O)=CC=1>>[O:20]=[C:19]1[N:3]2[CH:4]=[C:5]([C:6]([O:8][CH2:9][CH3:10])=[O:7])[CH:11]=[CH:12][C:2]2=[N:1][C:14]2[CH2:18][S:17][CH2:16][C:15]1=2Participants
4
Procedure
Ethyl 6-aminonicotinate (2.5 g., 0.015 mol), methyl 4-oxotetrahydrothiophene-3-carboxylate (6.2 g., 0.039 mol) and p-toluenesulfonic acid monohydrate (0.25 g) are thoroughly mixed and heated at 155°-160° C. under nitrogen for 90 minutes. The distillate is collected in a Dean-Stark trap. The residue is cooled, triturated with boiling ethanol and filtered. Recrystallization from methanol gives yellow crystals (1.2 g.), mp 183°-185° C.
Workup
- temperatureheated at 155°-160° C. under nitrogen for 90 minutes
- distillationThe distillate is collected in a Dean-Stark trap
- temperatureThe residue is cooled
- customtriturated with boiling ethanol
- filtrationfiltered
- customRecrystallization from methanol
- customgives yellow crystals (1.2 g.), mp 183°-185° C.
Sources & evidence
- ORD record
- ord-27f658963db94111a8a47e524d5fae78
- Source dataset
- uspto-grants-1982_06
- Patent number
- US04332947
Reaction notes
Loading…