Three-coordinate copper(II)-phenolate complexes

被引:120
作者
Jazdzewski, BA
Holland, PL
Pink, M
Young, VG
Spencer, DJE
Tolman, WB
机构
[1] Univ Minnesota, Dept Chem, Minneapolis, MN 55455 USA
[2] Univ Minnesota, Ctr Met Biocatalysis, Minneapolis, MN 55455 USA
关键词
D O I
10.1021/ic010615c
中图分类号
O61 [无机化学];
学科分类号
070301 ; 081704 ;
摘要
The re actions of LCuCl (L = 2,4-bis((2,6-diisopropylphenyl)imido)pentane (L-iPr), 2,4-bis((2,6-diisopropylphenyl)iniido)-3-chloropentane (L-CliPr)) with the phenolates TlOAr (Ar = C6H3Me2, C6H4OMe, C(6)H(4)tBu) and NaOC6H3(tBu)(2) were explored. Novel three-coordinate Cu(II)-phenolates, LCuOAr, were isolated from the reactions with the thallium phenolates and were characterized by X-ray crystallography and spectroscopy (UV-vis, EPR). The complexes feature short Cu-O(phenolate) distances (average Cu-O = 1.81 A) and, with one exception, irregular N-Cu-O(phenolate) angles that differ within each compound (15 degrees < Angstrom < 28 degrees, where Delta = <N-I-Cu-O-<N-2-Cu-O). The exception is (LCu)-Cu-iPr(OC(6)H(4)tBu), for which X-ray structures. at -100 and 25 degreesC differed due to an unusual reversible phase change with nonmerohedral twinning (2:1 ratio) in the low-temperature form. The high-temperature form has local C-2 nu, symmetry (Delta = 0 degrees), and upon cooling below the phase transition temperature (-8 +/-5 degreesC), lateral movement of the phenolate ligand (Delta = 17.6 degrees) and rotation of the phenolate plane by 10.7 degrees occurs. Resonance Raman spectroscopic data acquired for (LCu)-Cu-iPr(OC6H4tBu) corroborated assignment of phenolate --> Cu(II) LMCT character in the UV-vis spectra. Cyclic voltammetry experiments (THF, 0.5 M NBu4PF6) revealed negative E-1/2 values for the Cu(II)/Cu(I) couples relative to NHE, consistent with enhanced stabilization of the Cu(II) state by both the strongly electron donating beta -diketiminate ligand an. d the phenolates. Although thermally stable, the Cu(II) -phenolates are unusually reactive with dioxygen, albeit to give product(s) that have yet to be identified. In the reaction of (LCuCl)-Cu-iPr with NaOC6H3(tBu)(2) no Cu(II)-phenolate was observed. Instead, a Cu(I) complex was generated quantitatively by trapping with added isocyanide, [(LCuNC)-Cu-iPr(C6H3Me2)], along with 3,3',5,5'-tetra-tert-butyl-4,4'-dibenzoquinone and 2,6-di-tert-butylphenol in 27 +/- 3% and 46 +/- 6% yields, respectively, corresponding to the overall reaction 4L(iPr)Cu(II)Cl + 4NaOAr --> 4L(iPr)Cu(I) + 4NaCl + dibenzoquinone + 2(phenol).
引用
收藏
页码:6097 / 6107
页数:11
相关论文
共 55 条
[1]   COMPLETION AND REFINEMENT OF CRYSTAL-STRUCTURES WITH SIR92 [J].
ALTOMARE, A ;
CASCARANO, G ;
GIACOVAZZO, C ;
GUAGLIARDI, A .
JOURNAL OF APPLIED CRYSTALLOGRAPHY, 1993, 26 (pt 3) :343-350
[2]  
[Anonymous], PERSPECTIVES BIOINOR
[3]   AN EMPIRICAL CORRECTION FOR ABSORPTION ANISOTROPY [J].
BLESSING, RH .
ACTA CRYSTALLOGRAPHICA SECTION A, 1995, 51 :33-38
[4]  
*BRUNK AXS INC, SHELXTL V5 0 V5 U SO
[5]   SUBSTITUTED PHENOLS AS LIGANDS .4. 6-CO-ORDINATE AND 4-CO-ORDINATE COPPER(II) COMPLEXES WITH NITROGEN BASES - X-RAY CRYSTAL-STRUCTURE ANALYSIS OF BIS-(2-METHOXY-4-NITROPHENOLATO) BIS(PYRIDINE)COPPER(II) [J].
BULLOCK, JI ;
HOBSON, RJ ;
POVEY, DC .
JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 1974, (19) :2037-2043
[6]   Postural breathing pattern changes in patients with myotonic dystrophy [J].
Calabrese, P ;
Gryspeert, N ;
Auriant, I ;
Fromageot, C ;
Raphaël, JC ;
Lofaso, F ;
Benchetrit, G .
RESPIRATION PHYSIOLOGY, 2000, 122 (01) :1-13
[7]   CRYSTAL AND MOLECULAR-STRUCTURE OF AN UNSUBSTITUTED BIS(PHENOXO)-DERIVATIVE OF COPPER(II), THE [(CU(OPH)2(EN))2].2PHOH DIMER, WITH A NORMAL MAGNETIC-MOMENT AT ROOM-TEMPERATURE [J].
CALDERAZZO, F ;
MARCHETTI, F ;
PELIZZI, G ;
COLLIGIANI, A .
JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 1980, (08) :1419-1424
[8]  
Chaudhuri P, 1999, ANGEW CHEM INT EDIT, V38, P1095, DOI 10.1002/(SICI)1521-3773(19990419)38:8<1095::AID-ANIE1095>3.0.CO
[9]  
2-I
[10]   Aerobic oxidation of primary alcohols (including methanol) by copper(II)- and zinc(II)-phenoxyl radical catalysts [J].
Chaudhuri, P ;
Hess, M ;
Müller, J ;
Hildenbrand, K ;
Bill, E ;
Weyhermüller, T ;
Wieghardt, K .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1999, 121 (41) :9599-9610