TY - JOUR
T1 - Synthesis and characterization of the chromium(III) complexes of ethylene cross-bridged cyclam and cyclen ligands
AU - Maples, Danny L.
AU - Maples, Randall D.
AU - Hoffert, Wesley A.
AU - Parsell, Trenton H.
AU - Asselt, Allan van
AU - Silversides, Jon D.
AU - Archibald, Stephen J.
AU - Hubin, Timothy J.
PY - 2009/4/20
Y1 - 2009/4/20
N2 - Dichloro(4,10-dimethyl-1,4,7,10-tetraazabicyclo[5.5.2]tetradecane)chromium(III) chloride, Dichloro(4,10-dibenzyl-1,4,7,10-tetraazabicyclo[5.5.2]tetradecane) chromium(III) chloride, and Dichloro(4,11-dimethyl-1,4,8,11-tetraazabicyclo[6.6.2] hexadecane)chromium)(III) chloride have been prepared by the reaction of anhydrous chromium(III) chloride with the appropriate cross-bridged tetraazamacrocycle. Aquation of these complexes proved difficult, but Chlorohydroxo(4,11-dimethyl-1,4,8,11-tetraazabicyclo[6.6.2]hexadecane)chromium)(III) chloride was synthesized directly from chromium(II) chloride complexation followed by exposure or the reaction to air in the presence of water. The four complexes were characterized by X-ray crystal structure determination. All contain the chromium(III) ion in a distorted octahedral geometry and the macrocycle in the cis-V configuration, as dictated by the ethylene cross-bridge. Further characterization of the hydroxo complex reveals a magnetic moment of μeff = 3.95 B.M. and electronic absorbtions in acetonitrile at λmax = 583 nm (ε = 65.8 L/cm mol), 431 nm (ε = 34.8 L/cm mol) and 369 nm (ε = 17 L/cm mol).
AB - Dichloro(4,10-dimethyl-1,4,7,10-tetraazabicyclo[5.5.2]tetradecane)chromium(III) chloride, Dichloro(4,10-dibenzyl-1,4,7,10-tetraazabicyclo[5.5.2]tetradecane) chromium(III) chloride, and Dichloro(4,11-dimethyl-1,4,8,11-tetraazabicyclo[6.6.2] hexadecane)chromium)(III) chloride have been prepared by the reaction of anhydrous chromium(III) chloride with the appropriate cross-bridged tetraazamacrocycle. Aquation of these complexes proved difficult, but Chlorohydroxo(4,11-dimethyl-1,4,8,11-tetraazabicyclo[6.6.2]hexadecane)chromium)(III) chloride was synthesized directly from chromium(II) chloride complexation followed by exposure or the reaction to air in the presence of water. The four complexes were characterized by X-ray crystal structure determination. All contain the chromium(III) ion in a distorted octahedral geometry and the macrocycle in the cis-V configuration, as dictated by the ethylene cross-bridge. Further characterization of the hydroxo complex reveals a magnetic moment of μeff = 3.95 B.M. and electronic absorbtions in acetonitrile at λmax = 583 nm (ε = 65.8 L/cm mol), 431 nm (ε = 34.8 L/cm mol) and 369 nm (ε = 17 L/cm mol).
KW - Bridged tetraazamacrocycle
KW - Chromium(III)
KW - Cyclam
KW - Cyclen
UR - http://www.scopus.com/inward/record.url?scp=64349114474&partnerID=8YFLogxK
U2 - 10.1016/j.ica.2008.09.034
DO - 10.1016/j.ica.2008.09.034
M3 - Article
AN - SCOPUS:64349114474
SN - 0020-1693
VL - 362
SP - 2084
EP - 2088
JO - INORGANICA CHIMICA ACTA
JF - INORGANICA CHIMICA ACTA
IS - 6
ER -