TY - JOUR
T1 - Mononuclear Four-Coordinate Bis-Fluoride Bis-NHC Complexes of Chromium(II), Iron(II), and Cobalt(II)
AU - Acosta, Carlos M.
AU - Belov, Dmitry S.
AU - Lamur, Andy H.
AU - Brantley, Christi Anna L.
AU - Solans-Monfort, Xavier
AU - Rue, Kelly L.
AU - Christou, George
AU - Bukhryakov, Konstantin V.
N1 - Publisher Copyright:
© 2023 American Chemical Society.
PY - 2023/11/6
Y1 - 2023/11/6
N2 - The reaction between silylamido complexes of Cr(II), Fe(II), and Co(II) and IMes·2HF salt in the presence of IMes (IMes = 1,3-dimesitylimidazol-2-ylidene) led to isolation of Cr(IMes)2F2 (2-Cr), Fe(IMes)2F2 (2-Fe), and Co(IMes)2F2 (2-Co). X-ray structural studies revealed that 2-Cr adopts square planar geometry, while 2-Fe and 2-Co have distorted tetrahedral geometry. Magnetic susceptibility studies of 2-Cr, 2-Fe, and 2-Co were consistent with high-spin complexes, S = 2 for 2-Cr/2-Fe and S = 3/2 for 2-Co. We demonstrated that fluoride can be successfully exchanged for cyanide and azide using trimethylsilyl cyanide and trimethylsilyl azide (3-Fe and 4-Fe). DFT studies suggest that the preference of 2-Cr to adopt square planar geometry over tetrahedral is due to its d4 metal center, where four electrons fill the lower-lying d-orbitals.
AB - The reaction between silylamido complexes of Cr(II), Fe(II), and Co(II) and IMes·2HF salt in the presence of IMes (IMes = 1,3-dimesitylimidazol-2-ylidene) led to isolation of Cr(IMes)2F2 (2-Cr), Fe(IMes)2F2 (2-Fe), and Co(IMes)2F2 (2-Co). X-ray structural studies revealed that 2-Cr adopts square planar geometry, while 2-Fe and 2-Co have distorted tetrahedral geometry. Magnetic susceptibility studies of 2-Cr, 2-Fe, and 2-Co were consistent with high-spin complexes, S = 2 for 2-Cr/2-Fe and S = 3/2 for 2-Co. We demonstrated that fluoride can be successfully exchanged for cyanide and azide using trimethylsilyl cyanide and trimethylsilyl azide (3-Fe and 4-Fe). DFT studies suggest that the preference of 2-Cr to adopt square planar geometry over tetrahedral is due to its d4 metal center, where four electrons fill the lower-lying d-orbitals.
UR - http://www.scopus.com/inward/record.url?scp=85176502993&partnerID=8YFLogxK
U2 - 10.1021/acs.inorgchem.3c02442
DO - 10.1021/acs.inorgchem.3c02442
M3 - Article
C2 - 37876243
AN - SCOPUS:85176502993
SN - 0020-1669
VL - 62
SP - 18108
EP - 18115
JO - INORGANIC CHEMISTRY
JF - INORGANIC CHEMISTRY
IS - 44
ER -