TY - JOUR
T1 - “Pincer” Pyridine–Dicarbene–Iridium and -Ruthenium Complexes and Derivatives Thereof
AU - Danopoulos, Andreas A.
AU - Braunstein, Pierre
AU - Saßmannshausen, Jörg
AU - Pugh, David
AU - Wright, Joseph A.
N1 - Funding Information:
A. A. D. acknowledges support by a Special Account for Research Grant (S.A.R.G.) for the “Re‐initiation of Research” administered by the Rector of the National and Kapodistrian University of Athens. P. B. thanks the CNRS and the University of Strasbourg for support. J. S. acknowledges access to the research computing facility at King's College London, Rosalind (https://rosalind.kcl.ac.uk), delivered in partnership with the National Institute for Health Research (NIHR) Biomedical Research Centres at South London & Maudsley and Guy's & St. Thomas' NHS Foundation Trusts, and part‐funded by capital equipment grants from the Maudsley Charity (award 980) and Guy's & St. Thomas' Charity (TR130505). The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR, King's College London, or the Department of Health and Social Care.
Publisher Copyright:
© 2020 Wiley-VCH GmbH
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2020/9/22
Y1 - 2020/9/22
N2 - The cationic pincer-type complexes [IrI(CNMeC)L]X {CNMeC = [2,6-bis(2,6-diisopropylphenyl)imidazol-2-ylidene]-3,5-dimethylpyridine, L = CO, X = PF6 4; L = CH3CN, X = PF6 5; L = pyridine, X = BArF4, ArF = 3,5-bis-trifluoromethyl-phenyl 6}, that were obtained from [IrI(CNMeC)Cl] (1) by displacement of the chloride ligand were structurally characterized. Complexes 4 and 5 adopt square planar, in-plane distorted geometries, and in 6 the metal environment shows substantial pyramidalization. Theoretical calculations of the cations in 4 and 6 reproduce the experimental structures and rationalize their features. 1 undergoes oxidative transformations with CH2Cl2 to cis-[IrIII(CNMeC)(CH2Cl)Cl2] (7) and with PhICl2 to mer-[IrIII(CNMeC)Cl3] (8). The ruthenium derivatives trans-[RuII(CNC)Cl2L] {CNC = [2,6-bis(2,6-diisopropylphenyl)imidazol-2-ylidene]-pyridine, L = pyridine, 10} and [RuII(CNC)(η2,η2-nbd)](X)2. 2L (nbd = 2,5-norbornadiene, L = CH3CN, X = BF4 11), were prepared by the reaction of cis-trans-[RuCl2(nbd)(py)2] and trans-cis-[RuCl2(nbd)(pip)2] (pip = piperidine) with the ligand CNC, respectively; both adopt distorted octahedral structures. The back-bonding in 11 is comparable to that in its precursor complex, indicating minimal contribution of the NHC donors to this effect. Substitution of both chlorides in the known cis-[RuII(CNC)Cl2L] (L = PPh3) by azido ligands gave cis-[RuII(CNC)(N3)2L] (L = PPh3, 12), which by photolytic cleavage of the coordinated N3 failed to produce well-defined complexes.
AB - The cationic pincer-type complexes [IrI(CNMeC)L]X {CNMeC = [2,6-bis(2,6-diisopropylphenyl)imidazol-2-ylidene]-3,5-dimethylpyridine, L = CO, X = PF6 4; L = CH3CN, X = PF6 5; L = pyridine, X = BArF4, ArF = 3,5-bis-trifluoromethyl-phenyl 6}, that were obtained from [IrI(CNMeC)Cl] (1) by displacement of the chloride ligand were structurally characterized. Complexes 4 and 5 adopt square planar, in-plane distorted geometries, and in 6 the metal environment shows substantial pyramidalization. Theoretical calculations of the cations in 4 and 6 reproduce the experimental structures and rationalize their features. 1 undergoes oxidative transformations with CH2Cl2 to cis-[IrIII(CNMeC)(CH2Cl)Cl2] (7) and with PhICl2 to mer-[IrIII(CNMeC)Cl3] (8). The ruthenium derivatives trans-[RuII(CNC)Cl2L] {CNC = [2,6-bis(2,6-diisopropylphenyl)imidazol-2-ylidene]-pyridine, L = pyridine, 10} and [RuII(CNC)(η2,η2-nbd)](X)2. 2L (nbd = 2,5-norbornadiene, L = CH3CN, X = BF4 11), were prepared by the reaction of cis-trans-[RuCl2(nbd)(py)2] and trans-cis-[RuCl2(nbd)(pip)2] (pip = piperidine) with the ligand CNC, respectively; both adopt distorted octahedral structures. The back-bonding in 11 is comparable to that in its precursor complex, indicating minimal contribution of the NHC donors to this effect. Substitution of both chlorides in the known cis-[RuII(CNC)Cl2L] (L = PPh3) by azido ligands gave cis-[RuII(CNC)(N3)2L] (L = PPh3, 12), which by photolytic cleavage of the coordinated N3 failed to produce well-defined complexes.
KW - Carbene ligands
KW - Iridium
KW - Oxidative addition
KW - Pincer complexes
KW - Ruthenium
KW - Theoretical calculations
UR - http://www.scopus.com/inward/record.url?scp=85090456188&partnerID=8YFLogxK
U2 - 10.1002/ejic.202000429
DO - 10.1002/ejic.202000429
M3 - Article
AN - SCOPUS:85090456188
SN - 1434-1948
VL - 2020
SP - 3359
EP - 3369
JO - EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
JF - EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
IS - 35
ER -