TY - JOUR
T1 - Rhodium and iridium complexes of N-heterocyclic carbenes
T2 - Structural investigations and their catalytic properties in the borylation reaction
AU - Frey, Guido D.
AU - Rentzsch, Christoph F.
AU - von Preysing, Denise
AU - Scherg, Tobias
AU - Mühlhofer, Michael
AU - Herdtweck, Eberhardt
AU - Herrmann, Wolfgang A.
PY - 2006/12/15
Y1 - 2006/12/15
N2 - Bridged and unbridged N-heterocyclic carbene (NHC) ligands are metalated with [Ir/Rh(COD)2Cl]2 to give rhodium(I/III) and iridium(I) mono- and biscarbene substituted complexes. All complexes were characterized by spectroscopy, in addition [Ir(COD)(NHC)2][Cl,I] [COD = 1,5-cyclooctadiene, NHC = 1,3-dimethyl- or 1,3-dicyclohexylimidazolin-2-ylidene] (1, 4), and the biscarbene chelate complexes 12 [(η4-1,5-cyclooctadiene)(1,1′-di-n-butyl-3,3′-ethylene-diimidazolin-2,2′-diylidene)iridium(I) bromide] and 14 [(η4-1,5-cyclooctadiene)(1,1′-dimethyl-3,3′-o-xylylene-diimidazolin-2,2′-diylidene)iridium(I) bromide] were characterized by single crystal X-ray analysis. The relative σ-donor/π-acceptor qualities of various NHC ligands were examined and classified in monosubstituted NHC-Rh and NHC-Ir dicarbonyl complexes by means of IR spectroscopy. For the first time, bis(carbene) substituted iridium complexes were used as catalysts in the synthesis of arylboronic acids starting from pinacolborane and arene derivatives.
AB - Bridged and unbridged N-heterocyclic carbene (NHC) ligands are metalated with [Ir/Rh(COD)2Cl]2 to give rhodium(I/III) and iridium(I) mono- and biscarbene substituted complexes. All complexes were characterized by spectroscopy, in addition [Ir(COD)(NHC)2][Cl,I] [COD = 1,5-cyclooctadiene, NHC = 1,3-dimethyl- or 1,3-dicyclohexylimidazolin-2-ylidene] (1, 4), and the biscarbene chelate complexes 12 [(η4-1,5-cyclooctadiene)(1,1′-di-n-butyl-3,3′-ethylene-diimidazolin-2,2′-diylidene)iridium(I) bromide] and 14 [(η4-1,5-cyclooctadiene)(1,1′-dimethyl-3,3′-o-xylylene-diimidazolin-2,2′-diylidene)iridium(I) bromide] were characterized by single crystal X-ray analysis. The relative σ-donor/π-acceptor qualities of various NHC ligands were examined and classified in monosubstituted NHC-Rh and NHC-Ir dicarbonyl complexes by means of IR spectroscopy. For the first time, bis(carbene) substituted iridium complexes were used as catalysts in the synthesis of arylboronic acids starting from pinacolborane and arene derivatives.
KW - Carbene complexes
KW - Catalysis
KW - Coupling
KW - Hydroborations
KW - Iridium
KW - Rhodium
UR - http://www.scopus.com/inward/record.url?scp=34547167667&partnerID=8YFLogxK
U2 - 10.1016/j.jorganchem.2006.08.099
DO - 10.1016/j.jorganchem.2006.08.099
M3 - Article
AN - SCOPUS:34547167667
SN - 0022-328X
VL - 691
SP - 5725
EP - 5738
JO - Journal of Organometallic Chemistry
JF - Journal of Organometallic Chemistry
IS - 26
ER -