TY - JOUR
T1 - Synthesis and spectroscopic characterization of five-coordinate complexes of Ni2+ based on N3-macrocycles and salicylaldiminates. Crystal structure of [Ni(9-Me-N3-mc)(OC6H4CH=NC6H 5-o)](ClO4) (9-Me-N3-mc=2,4,4,9-tetramethyl-1,5,9-triazacyclododec-1-ene)
AU - Santana, M. Dolores
AU - Rufete, Antonio
AU - Sánchez, Gregorio
AU - García, Gabriel
AU - López, Gregorio
AU - Casabó, Jaume
AU - Molins, Elíes
AU - Miravitlles, Carles
PY - 1997/2/1
Y1 - 1997/2/1
N2 - Five-coordinate nickel(II) complexes of the type [Ni(N3-macrocycle)(OC6H4CH=NR-o)]+ (N3-macrocycle=2,4,4-trimethyl-1,5,9-triazacyclododec-1-ene, N3-mc, or its 9-methyl derivative, 9-Me-N3-mc) have been prepared by reaction between [{Ni(N3-macrocycle)(μ-OH)}2]+ and the appropriate arylsalicylaldimine. An X-ray diffraction study carried out with the complex [Ni(9-Me-N3-mc)(OC6H4CH=NC6H 5-o)](ClO4) has established that the Ni atom presents a square pyramidal coordination and is displaced 0.30 Å out of the basal plane towards the apical N1 atom (a=8.552(2), b=33.398(3), c=9.630(3) Å, β=91.67(1)°, monoclinic, space group P21/a, V=2749(1) Å3, Z=4, Dcalc=1.40 g cm-3, R=0.058, Rw=0.066). These paramagnetic species have been studied by 1H NMR. The characteristic pattern of N3-mc and 9-Me-N3-mc has been established and the specific assigment of salicylaldimine resonances has been achieved by NOE measurements. The solution electronic spectra of the complexes are also suggestive of five-coordinate geometry in solution.
AB - Five-coordinate nickel(II) complexes of the type [Ni(N3-macrocycle)(OC6H4CH=NR-o)]+ (N3-macrocycle=2,4,4-trimethyl-1,5,9-triazacyclododec-1-ene, N3-mc, or its 9-methyl derivative, 9-Me-N3-mc) have been prepared by reaction between [{Ni(N3-macrocycle)(μ-OH)}2]+ and the appropriate arylsalicylaldimine. An X-ray diffraction study carried out with the complex [Ni(9-Me-N3-mc)(OC6H4CH=NC6H 5-o)](ClO4) has established that the Ni atom presents a square pyramidal coordination and is displaced 0.30 Å out of the basal plane towards the apical N1 atom (a=8.552(2), b=33.398(3), c=9.630(3) Å, β=91.67(1)°, monoclinic, space group P21/a, V=2749(1) Å3, Z=4, Dcalc=1.40 g cm-3, R=0.058, Rw=0.066). These paramagnetic species have been studied by 1H NMR. The characteristic pattern of N3-mc and 9-Me-N3-mc has been established and the specific assigment of salicylaldimine resonances has been achieved by NOE measurements. The solution electronic spectra of the complexes are also suggestive of five-coordinate geometry in solution.
KW - Crystal structures
KW - Macrocycle complexes
KW - Nickel complexes
KW - Pentacoordinate complexes
M3 - Article
VL - 255
SP - 21
EP - 27
JO - Inorganica Chimica Acta
JF - Inorganica Chimica Acta
SN - 0020-1693
IS - 1
ER -