Metal/organo relay catalysis in a one-pot synthesis of methyl 4-aminopyrrole-2-carboxylates from 5-methoxyisoxazoles and pyridinium ylides.
Methyl 4-aminopyrrole-2-carboxylates were synthesized in one-pot mode by the relay catalytic cascade reaction of 5-methoxyisoxazoles with pyridinium ylides by the use of a FeCl2/Et3N binary catalytic system leading to 1-(5-methoxycarbonyl-1H-pyrrol-3-yl)pyridinium salts followed by hydrazinolysis. The approach permits the introduction of a substituent at the pyrrole nitrogen via a nucleophilic reaction of the pyrrolylpyridinium ylide derived from the salt. Catalytic reduction of the ylides gives methyl 4-piperidinopyrrole-2-carboxylates.
Institute of Chemistry, Saint-Petersburg State University, Universitetskii pr. 26, 198504 St.-Petersburg, Russia. a.khlebnikov@spbu.ru.
Ekaterina E
EE
Galenko
Olesya A
OA
Tomashenko
Alexander F
AF
Khlebnikov
Mikhail S
MS
Novikov
D002264:Carboxylic Acids / Q000737:chemistry*; D002384:Catalysis; D061565:Cycloaddition Reaction; D007555:Isoxazoles / Q000737:chemistry*; D008670:Metals / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D011726:Pyridinium Compounds / Q000737:chemistry*; D011758:Pyrroles / Q000737:chemistry*
D002264:Carboxylic Acids; D007555:Isoxazoles; D008670:Metals; D011726:Pyridinium Compounds; D011758:Pyrroles