TY - JOUR
T1 - Synthesis and Copper Coordination Chemistry of Hindered 1,4,7-Triazacyclononane Ligands with Amide Appendages
AU - Berreau, Lisa M.
AU - Halfen, Jason A.
AU - Young, Victor G.
AU - Tolman, William B.
PY - 1998
Y1 - 1998
N2 - Copper complexes of the new ligands1a LPiv and LRAmR' that comprise 1,4-diisopropyl-1,4,7-triazacyclononanes linked to secondary and tertiary amide groups were prepared and characterized, with a particular view toward evaluating amide structural, spectroscopic, and potential hydrogen-bonding influences of relevance to ongoing copper-dioxygen reactivity studies. X-ray crystal structures of the Cu(I) complexes [LCu(CH3CN)]X (L = LHAmMe, X = ClO4; L = LPiv, X = CF3SO3) revealed typical 4-coordinate geometries with the amide dangling free, while those of the Cu(II) compounds [LCuCl]X (L = LHAmMe, X = ClO4; L = LMeAmH, X = PF6) and [LPivCu(O3-SCF3)]O3SCF3 showed 5-coordinate square pyramidal geometries with the amide coordinated to the metal via its carbonyl oxygen atom. Analysis of FTIR spectra of the aforementioned compounds and the carbon monoxide adducts [LMeAmR'Cu(CO)]SbF6 (R' = H or Me) allowed (i) identification of signatures of amide structural features, hydrogen bonding, and metal coordination and (ii) classification of the amide ligands as generally electron withdrawing relative to alkyl-substituted counterparts (e.g., 1,4,7-triisopropyl-1,4,7-triazacyclononane).
AB - Copper complexes of the new ligands1a LPiv and LRAmR' that comprise 1,4-diisopropyl-1,4,7-triazacyclononanes linked to secondary and tertiary amide groups were prepared and characterized, with a particular view toward evaluating amide structural, spectroscopic, and potential hydrogen-bonding influences of relevance to ongoing copper-dioxygen reactivity studies. X-ray crystal structures of the Cu(I) complexes [LCu(CH3CN)]X (L = LHAmMe, X = ClO4; L = LPiv, X = CF3SO3) revealed typical 4-coordinate geometries with the amide dangling free, while those of the Cu(II) compounds [LCuCl]X (L = LHAmMe, X = ClO4; L = LMeAmH, X = PF6) and [LPivCu(O3-SCF3)]O3SCF3 showed 5-coordinate square pyramidal geometries with the amide coordinated to the metal via its carbonyl oxygen atom. Analysis of FTIR spectra of the aforementioned compounds and the carbon monoxide adducts [LMeAmR'Cu(CO)]SbF6 (R' = H or Me) allowed (i) identification of signatures of amide structural features, hydrogen bonding, and metal coordination and (ii) classification of the amide ligands as generally electron withdrawing relative to alkyl-substituted counterparts (e.g., 1,4,7-triisopropyl-1,4,7-triazacyclononane).
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U2 - 10.1021/ic971115f
DO - 10.1021/ic971115f
M3 - Article
AN - SCOPUS:0000289826
SN - 0020-1669
VL - 37
SP - 1091
EP - 1098
JO - Inorganic chemistry
JF - Inorganic chemistry
IS - 5
ER -