TY - JOUR
T1 - Iso‐anellated thienopyrroles
T2 - The chemistry of 5,6‐dihydro‐4H‐thieno[2,3‐c]pyrroles and 5H‐thieno[2,3‐c]pyrroles
AU - Feijen, J.
AU - Wynberg, Hans
PY - 1970/1/1
Y1 - 1970/1/1
N2 - The ring closure reaction of methyl 2,3‐bis(chloromethyl)thiophene‐5‐carboxylate with several primary amines gives a series of 5,6‐dihydro‐4H‐thieno‐[2,3‐c]pyrroles. Oxidation of some of these dihydro compounds, using aqueous hydrogen peroxide in methanol, furnishes the corresponding N‐oxides. When the nitrogen atom possesses an aromatic substituent and the oxidation is carried out with aqueous hydrogen peroxide in formic acid, Meisenheimer1 rearrangement products instead of N‐oxides are formed. The structure of one of the Meisenheimer products was elucidated by an independent synthesis of its degradation product. 5H‐Thieno[2,3‐c]pyrroles are prepared by three separate methods: (a) dehydration of the N‐oxides; (b) autoxidation of the dihydrothieno[2,3‐c]‐pyrroles; (c) dehydrogenation of the dihydro compounds with chloranil.
AB - The ring closure reaction of methyl 2,3‐bis(chloromethyl)thiophene‐5‐carboxylate with several primary amines gives a series of 5,6‐dihydro‐4H‐thieno‐[2,3‐c]pyrroles. Oxidation of some of these dihydro compounds, using aqueous hydrogen peroxide in methanol, furnishes the corresponding N‐oxides. When the nitrogen atom possesses an aromatic substituent and the oxidation is carried out with aqueous hydrogen peroxide in formic acid, Meisenheimer1 rearrangement products instead of N‐oxides are formed. The structure of one of the Meisenheimer products was elucidated by an independent synthesis of its degradation product. 5H‐Thieno[2,3‐c]pyrroles are prepared by three separate methods: (a) dehydration of the N‐oxides; (b) autoxidation of the dihydrothieno[2,3‐c]‐pyrroles; (c) dehydrogenation of the dihydro compounds with chloranil.
UR - http://www.scopus.com/inward/record.url?scp=84977378786&partnerID=8YFLogxK
U2 - 10.1002/recl.19700890611
DO - 10.1002/recl.19700890611
M3 - Article
AN - SCOPUS:84977378786
SN - 0165-0513
VL - 89
SP - 639
EP - 657
JO - Recueil des Travaux Chimiques des Pays‐Bas
JF - Recueil des Travaux Chimiques des Pays‐Bas
IS - 6
ER -