NEW SYNTHESES OF PYRROLO[3,4-B]INDOLES, BENZO[B]FURO[2,3-C]PYRROLES, AND BENZO[B]THIENO [2,3-C]PYRROLES UTILIZING THE REACTION OF MUNCHNONES (1,3-OXAZOLIUM-5-OLATES) WITH NITROHETEROCYCLES
Gw. Gribble et al., NEW SYNTHESES OF PYRROLO[3,4-B]INDOLES, BENZO[B]FURO[2,3-C]PYRROLES, AND BENZO[B]THIENO [2,3-C]PYRROLES UTILIZING THE REACTION OF MUNCHNONES (1,3-OXAZOLIUM-5-OLATES) WITH NITROHETEROCYCLES, Synlett, (10), 1998, pp. 1061
1,3-Dipolar cycloaddition of munchnones (mesoionic 1,3-oxazolium-5-ola
tes) 3 and 4 with 2- and 3-nitroindoles, 2-nitrobenzo[b]furan, and 3-n
itrobenzo[b]thiophene affords the corresponding pyrrolo[3,4-b]indoles,
benzo[b]furo[2,3-c]pyrroles, and benzo[b]thieno[2,3-c]pyrroles, respe
ctively, in one operation in good to excellent yields.