Microwave-assisted C-H bond activation: a rapid entry into functionalized heterocycles.
[reaction: see text] Microwave irradiation strongly accelerates the rhodium-catalyzed intramolecular coupling of a benzimidazole C-H bond to pendant alkenes. The cyclic products were formed in moderate to excellent yields with reaction times less than 20 min. Additionally, the use of microwave irradiation allowed the reactions to be performed without any solvent purification and with minimal precautions to exclude air.
Tan
Kian L
KL
Center for New Directions in Organic Synthesis, Department of Chemistry, University of California-Berkeley, Berkeley, California 94720, USA.
Vasudevan
Anil
A
Bergman
Robert G
RG
Ellman
Jonathan A
JA
Souers
Andrew J
AJ
D000475:Alkenes / Q000737:chemistry; D001562:Benzimidazoles / Q000737:chemistry; D002384:Catalysis; D003500:Cyclization; D006571:Heterocyclic Compounds / Q000138:chemical synthesis*; D008872:Microwaves; D009942:Organometallic Compounds / Q000737:chemistry; D012238:Rhodium / Q000737:chemistry
D000475:Alkenes; D001562:Benzimidazoles; D006571:Heterocyclic Compounds; D009942:Organometallic Compounds; D012238:Rhodium