presence of 2-mercaptoethanol to yield N-aryl-5,6-dihydro-4-oxo-4H-thieno[3,4-c]pyrroles 2 and N-aryl-4-arylimino-5,6-dihydro-4H-thieno[3,4-c]pyrroles 3, while thiophene 2,3-dicarbaldehyde 4 reacts with aromatic amines to give N-aryl-5,6-dihydro-6-oxo-4H-thieno[2,3-c]pyrroles 5 in good yields. Labeling experiments and nmr spectral analysis give evidences for the possible reaction mechanism.
                                    噻吩-3,4-二甲醛1在
2-巯基乙醇的存在下反应生成N-芳基-5,6-二氢-4-氧代-4 H-
噻吩并[3,4- c ]
吡咯2和N-芳基- 4-芳基-5,6-二氢-4 H-
噻吩并[3,4- c ]
吡咯3,而
噻吩2,3-二
甲醛4与芳族胺反应生成N-芳基-5,6-二氢-6- oxo-4 H -thieno [2,3- c ]
吡咯5的收率高。标记实验和核磁共振光谱分析为可能的反应机理提供了证据。