4048 Inorg. Chem. 1981, zyxwvu 20,4048-4053 Contribution from the Department of Chemistry and Biochemistry, James Cook University of North Queensland, Queensland, 48 1 1, Australia, the Laboratorium fur Anorganische Chemie, ETH, CH-8092 Zurich, Switzerland, and the Department of Chemistry, The Polytechnic of North London, Holloway, London, N7 8DB, United Kingdom Interaction of Cobalt(II), Nickel(II), and Copper(I1) with a New Macrocyclic Ligand Incorporating 04N4Heteroatoms. Synthetic, Solution, and X-ray Diffraction Studies KENNETH R. ADAM,Ia GIORGIO ANDEREGG,lb KIM HENRICK,” ANTHONY J. LEONG,la LEONARD F. LINDOY,*la HYACINTH C. LIP,Ia MARY McPARTLIN,Ic ROLAND J. SMITH,la and PETER A. TASKER*IC Received February zyxwvutsrqpo 18, 1981 The interaction of cobalt(II), nickel(II), and copper(I1) with a new 28-membered 04N4 macrocycle (L) has been investigated, and 1:l complexes with each of these metal ions have been isolated. From physical measurements, the cobalt(I1) and nickel(I1) complexes have been assigned octahedral or pseudooctahedral geometries. Potentiometric studies on these complexes in 95% methanol zyxwvutsrqpon (I zyxwvutsrqpo = 0.1, (CH3),NC1) indicate log K values for the equilibrium M2+ + L + ML2+ of 10.13 zyx f 0.10 for cobalt and 12.6 f 0.09 for nickel. These values are higher than those obtained for the corresponding complexes of related 17- and 18-membered 02N3-donor macrocycles. The trends in the respective log K values indicate coordination of all four nitrogens of the 28-membered macrocycle to the above metal ions. An X-ray diffraction study of NiL(NCS),.(di- methylformamide) has been undertaken. The nickel ion has a N,-mrdination sphere with the four nitrogens of the macrocycle and the two thiocyanate nitrogens coordinating in a pseudooctahedral arrangement. The two thiocyanate ligands occupy cis positions: space group Pbcn, a = 20.268 (3) A, b = 12.236 (2) A, c = 17.443 (3) A, R = 0.053 for 1827 four-circle diffractometer data with I > 3 4 0 . The other noncrystallographic studies for this complex are thus consistent with the X-ray structure. Introduction In contrast to the metal ion chemistry of macrocyclic ligands incorporating all ether-oxygen or all nitrogen donor atoms, the chemistry of mixed oxygen-nitrogen donor macrocycles has received less attention2 As part of a program involving the study of such macrocycles as potential metal-ion selective reagents, synthetic, structural, kinetic, and thermodynamic aspects of the interaction of macrocycles of types 1 and 2 with 1 2 cobalt( II), nickel( 11), and copper( 11) have been in~estigated.~-’O (1) (a) James Cook University. (b) ETH, Zurich. (c) Polytechnic of North London. (2) Izatt, R. M., Christensen, J. J., Eds. “Synthetic Multidentate Macro- cyclic Compounds”; Academic Press: New York, 1978. Lindoy, L. F. Chem. zyxwvutsrqpon SOC. Rev. 1975, 4, 421. (3) Armstrong, L. G.; Grimsley, P. G.; Lindoy, L. F.; Lip, H. C.; Norris, V. A,; Smith, R. J. Inorg. Chem. 1978, 17, 2350. (4) Ekstrom, A,; Lindoy, L. F.; Lip, H. C.; Smith, R. J.; Goodwin, H. J.; McPartlin, M.; Tasker, P. A. J. Chem. SOC., Dalton Tram. 1979, 1027. (5) Ekstrom, A,; Lindoy, L. F.; Smith, R. J. Inorg. Chem. 1980, 19, 724. (6) Anderegg, G.; Ekstrom, A.; Lindoy, L. F.; Smith, R. J. J. Am. Chem. Soc. 1980, 102, 2670. Adam, K. R.; Lindoy, L. F.; Smith, R. J.; Anderegg, G.; Henrick, K.; McPartlin, M.; Tasker, P. A. J. Chem. Soc., Chem. Commun. 1979, 812. (7) Adam, K. R.; Anderegg, G.; Lindoy, L. F.; Lip, H. C.; McPartlin, M.; Rea, J. H.; Smith, R. J.; Tasker, P. A. Inorg. Chem. 1980, 19, 2956. (8) Lindoy, L. F.; Lip, H. C.; Rea, J. H.; Smith, R. J.; Henrick, K.; McPartlin, M.; Tasker, P. A. Inorg. Chem. 1980, 19, 3360. (9) Adam, K. R.; Lindoy, L. F.; Lip, H. C.; Rea, J. H.; Skeltm, B. W.; White. A. H. J. Chem. Soc.. Dalton Trans. 1980. 74. Adam. K. R.: A potentially useful macrocyclic ring-size effect was observed on interaction of nickel with the macrocycles of type 1;6 along this series of 14- to 17-membered macrocycles, a peak in the thermodynamic stabilities occurred at the 16-membered ring complex. With cobalt(I1) or copper(II), no clearly defined ring-size discrimination effects were observed and this dif- ference has been rationalized in terms of the proposed struc- tures of these comple~es.~~~ As an extension of these previous studies, we now discuss the results of an investigation involving the interaction of the larger-ring macrocycle 3 (incorporating eight potential donor atoms) with cobalt(II), nickel(II), and copper(I1). i’ 3 Experimental Section Synthesis and Characterization of the Complexes. Conductance measurements were determined with the use of a Philips conductivity bridge type PR 9500. All measurements were recorded at 25 OC on solutions of approximately M. Infrared spectra were recorded with the use of Nujol mulls with a Perkin-Elmer 197 spectropho- tometer. All spectra were calibrated with a polystyrene standard. Solution spectra (in dimethyl sulfoxide) were obtained with the use of a Beckman ACTA-IV spectrophotometer. Solid-state spectra were determined on the above spectrophotometer using mulls of the com- pound spread on filter paper. Magnetic moments were determined with the use of a Faraday balance calibrated against Hg[Co(NCS),]. ‘H NMR spectra were determined with a Jeol JHN-NM-100 spec- trometer, and spectra were obtained on a Jeol JNM FX-60Q wectrometer. The mass suectra were obtained with a Jeol JMS-D100 Lindoy, L. F.; Lip, H. C.; Smith, R. J.; unpublished work. spectrometer and a Kratos MS50 (field-desorption)spectrometer. We (10) This “dimeric” product was originally erroneously assumed to have a “monomeric” structure of type 1 (m = n = 2)-see: Grimsley, P. G.; Lindoy, L, F.; Lip, H, c,; Smith, R, J,; Baker, J, T, J, (-hem, 1977, 30, 2095. However, the monomeric form can be isolated from the filtrate as its dihydrochloride and purified as described in the above D~. A, ~ ~ l l of the Department of Bioc-,&istry,-lmperial college, London, for determining the field-desorption spectrum. Microanalyses for c, H, and were determined by Mr. J. Kent, Department Of Chemistry, University of Queensland. Metal analyses were determined reference; alternatively, the material-remaining in the filtrate can be complexed to nickel chloride, the resulting complex recrystallized from methanol, and pure monomer obtained by addition of excess EDTA to an aqueous solution at pH 10 of the recrystallized complex. The free macrocycle which separates can be extracted into chloroform and iso- lated as its dihydrochloride on passing dry HCI through the chloroform extract. using a Varian-AA6 atomic absorption spectrophotometer. compounds gave satisfactory analytical data and these are listed in supplementary ~ ~ b l ~ SI. Spectrophotometrictitrations were performed by direct incremental addition of known weights of the ligand to the spectrophotometric cell containing the respective metal perchlorates in dimethyl sulfoxide. All 0020-1669/81/1320-4048$01.25/0 0 1981 American Chemical Society