Control of molecular architecture by use of the appropriate ligand isomer: a mononuclear "corner-type" versus a tetranuclear [2 x 2] grid-type cobalt(III) complex

Employing two isomeric pyrazine-based ligands a [2 x 2] grid-type tetranuclear cobalt(III) complex, incorporating doubly deprotonated (La)2- ligands, and a "corner-type" mononuclear cobalt(III) complex, incorporating neutral H2Lp ligands in a zwitterionic form, have been synthesised and structurally characterised.     

Synthesis and characterisation of cobalt(II), cobalt(III) and rhodium(III) complexes ofN,N′, N″, N‴-tetra(2-cyanoethyl) cyclam [TCEC] andN,N′, N″, N‴-tetra)3-aminopropyl) cyclam [TAPC]

Summary Complexes of cobalt(II), cobalt(III) and rhodium(III) with TCEC and TAPC have been synthesised. TCEC with cobalt(II) gave [Co(TCEC)Br]Br and [Co(TCEC)Cl]Cl, five coordinate high spin square pyramid complexes, but the corresponding cobalt(III) complex could not be characterised. Rhodium(III) gave a six coordinate [Rh(TCEC)Cl₂]Cl complex, in which the two coordinated chlorides have acis-geometry and the four pendant arms lie on one side of the N₄ plane with none of the —CN groups coordinated TAPC on the other hand gives the cobalt(III) complex, [Co(TAPC)Br]Br₂, in which one of the amino groups of the four pendant arms is coordinated to cobalt. Rhodium(III) with TAPC gave [Rh(TAPC)Cl]Cl₂ in which one axial site is occupied by the amino group of one of the pendant arms and the other by Cl^–.     

Transition metal ion complexes of thiosemicarbazones derived from 2-acetylpyridine. Part 3. The 3-hexamethyleneimine derivative

Summary Metal ion complexes of the thiosemicarbazone, 3-hexamethyleneimine-3-thiocarboxylic acid-2-[1-(2-pyridyl)-ethylidene]hydrazide (HLhexim) have been prepared and spectrally characterized. HLhexim coordinates primarily as the deprotonated tridentate ligand (i.e., pyridylN, azomethineN, and thione sulphur). The air oxidised cobalt(III) complex, [Co(LHexim)₂] (BF₄), was isolated from the preparation with cobalt(II) tetrafluoroborate, but other cobalt(II) salts yielded tetrahedral cobalt(II) compounds. Planar nickel(II) and copper(II) complexes were isolated from preparations with halide salts. Significant differences in the spectral properties of the various complexes are observed when compared to other thiosemicarbazones prepared from 2-acetylpyridine.     

An example of O2 binding in a cobalt(II) corrole system and high-valent cobalt-cyano and cobalt-alkynyl complexes

The novel cobalt corrolazine (Cz) complexes (TBP)(8)CzCoCN (1) and (TBP)(8)CzCo(CCSiPh(3)) (2) have been synthesized and examined in light of the recent intense interest regarding the role of corrole ligands in stabilizing high oxidation states. In the case of 2, the molecular structure has been determined by X-ray crystallography, revealing a short Co[bond]C distance of 1.831(4) A and an intermolecular pi-stacking interaction between Cz ring planes, and this structure has been analyzed in regards to the electronic configuration. By a combination of spectroscopic techniques it has been shown that 1 is best described as a cobalt(III)[bond]pi-cation-radical complex, whereas 2 is likely best represented as the resonance hybrid (Cz)Co(IV)(CCSiPh(3)) <--> (Cz+*)Co(III)(CCSiPh(3)). The reduced cobalt(II) complex, [(TBP)(8)CzCo(II)(py)](-), has been generated in situ and shown to bind dioxygen at low temperature to give [(TBP)(8)CzCo(III)(py)(O(2))](-). For the reduced complex [(TBP)(8)CzCo(II)(py)](-), the EPR spectrum in frozen solution is indicative of a low-spin cobalt(II) complex with a d(z)2 ground state. Exposure of [(TBP)(8)CzCo(II)(py)](-) to O(2) leads to the reversible formation of the cobalt(III)-superoxo complex [(TBP)(8)CzCo(III)(py)(O(2))](-), which has been characterized by EPR spectroscopy. VT-EPR measurements show that the dioxygen adduct is stable up to T approximately 240 K. This work is the first observation, to our knowledge, of O(2) binding to a cobalt(II) corrole.     

PHOTOPRODUCTION OF HYDROGEN FROM LINKED CHROMOPHORES

Abstract On irradiation of solutions of anthryl-substituted cobalt(III) cage complexes, [(l-(anthryl-9-methylamino)-8-methyl-3,6,10,13,16,19-hexaazabicyclo [6.6.6] eicosane) cobalt(III)]³⁺ or [(l-(4-an-thryl-9)-3-aza-butyl-l-amino)-8-methyl-3,6,10,13,16,19-hexaazabicyclo [6.6.6] eicosane)cobalt (III)]³* in the presence of ethylenediaminetetraacetic acid and platinum catalysts hydrogen was produced. These complexes act as coupled photosensitizers (anthracene moiety) and electron relays (cobalt cage) to produce H₂ via energy trapping and intramolecular electron transfer initially. The intensity of fluorescence and the photochemical reactivity favour the latter complex and the excited singlet state of the anthracene chromophore is invoked as the intermediate state leading to the reduction of Co(III) to Co(II).     

Cobalt(III) complexes of [3(5)] adamanzane, 1,5,9,13-tetraazabicyclo[7.7.3]nonadecane. Report of an inert, chelate hydrogen carbonate ion

Three cobalt(III) complexes of the macrocyclic tetraamine [3(5)]adamanzane (1,5,9,13-tetraazabicyclo[7.7.3]nonadecane) were isolated as salts. The X-ray crystal structures were solved for the compounds [Co([3(5)]adz)(CO(3))]AsF(6) (1b), [Co([3(5)]adz)(HCO(3))]ZnBr(4).H(2)O (2a), and [Co([3(5)]adz)(SO(4))]AsF(6).H(2)O (3a). The coordination geometry around the cobalt(III) ion is a distorted octahedron with the inorganic ligands at cis-positions. Complex 2 is the second example of a cobalt(III) complex for which the X-ray structure shows a chelate binding mode of the hydrogen carbonate entity. The pK(a) value of the [Co([3(5)]adz)(HCO(3))](2+) ion (2) was determined spectrophotometrically to be 0.27 (25 degrees C, I = 5.0 M). The protonation appears to occur at the noncoordinated carbonyl oxygen atom of the carbonate group, with hydrogen bonding to the crystal water molecule. Evidence is presented for this oxygen atom as the site of protonation in solution as well. In 5.0 M CF(3)SO(3)H a slow reaction of the carbonato complex, quantitatively yielding the [Co([3(5)]adz)(H(2)O)(2)](3+) ion, was observed. k(obs) = 7.9(1) x 10(-)(6) s(-)(1) at 25 degrees C.     

Solvent Extraction of Heavy Metals with a 23-Membered Macrocyclic Ionophore Attached with BF 2 + -Capped Cobalt(III) Complex

A new (E, E)-dioxime cobalt(III) complex [Co(HL)₂pyCl]containing four 23-membered macrocyclic ionophores has beenprepared. The cobalt(III) complex [Co(LBF₂)₂pyCl]bridged with BF₂ ⁺ was prepared using the precursorcobalt(III) complex and boron trifluoride ethyl ethercomplex. The solvent extraction of heavy metal cationssuch as Ni²⁺, Cu²⁺, Zn²⁺, Hg²⁺ and Pb²⁺ by the BF₂ ⁺-capped cobalt(III) complex has been investigated. The structure of the complexes is proposedaccording to elemental analyses, ¹H and ¹³C-NMR, IRand mass spectral data.     

Synthesis of a chelating hexadentate ligand with a P3N3 donor set. Crystal and molecular structure of [OC-6-22]-[Co{(RP*,RP*,RP*)-CH3C(CH2PPhC6H4NH2-2)3}](PF6)3

The first structurally authenticated example of a hexadentate chelating tertiary phosphine in which all six donors are bound to a single metal centre is described. The multidentate ligand (RP*,RP*,RP*)- and (RP*,RP*,SP*)-CH3C(CH2PPhC6H4NH2-2)3 has been prepared in 80% yield via the reaction of five equivalents of sodium (2-aminophenyl)phenylphosphide (generated in situ from (2-aminophenyl)phenylphosphine and sodium in thf) with 1,1,1-tri(bromomethyl)ethane in thf. The diastereomeric mixture has been complexed to cobalt(III) and the resulting pair of complexes, viz. [Co{(RP*,RP*,RP*)-CH3C(CH2PPhC6H4NH2-2)3}]Cl3 and [CoCl{(RP*,RP*,SP*)-CH3C(CH2PPhC6H4NH2-2)3}]Cl2, separated by ion exchange chromatography. The structure of the former (as the corresponding hexafluorophosphate salt) has been confirmed by X-ray crystallography and clearly shows all six donors of the P3N3 ligand coordinated to a single cobalt(III) centre. The related hexadentate ligand with internal N donors and terminal diphenylphosphino groups, viz. CH3C(CH2NHC6H4PPh2-2)3, has also been synthesised, albeit in low yield, via the reaction of [Li(tmeda)][2-NHC6H4PPh2] (generated in situ from (2-aminophenyl)diphenylphosphine, n-butyllithium and tmeda in diethyl ether) with 1,1,1-tri(iodomethyl)ethane in thf. No formation of a P3N3 ligand has been observed when either Na[2-PPhC6H4NH2] or [Li(tmeda)][2-NHC6H4PPh2] is reacted with the related tripodal substrate 1,1,1-tris(tolyl-4-sulfonyloxymethyl)ethane in thf. Rather the P-methyloxetane (+/-)-[3-{(2-aminophenyl)phenylphosphinomethyl}]-3-methyloxetane and the sulfonamide 2-(4-CH3C6H4SO2)NHC6H4PPh2 and the corresponding N-methyloxetane [3-{(2-diphenylphosphinophenyl)aminomethyl}]-3-methyloxetane have been isolated from the respective reactions. The structure of the sulfonamide has been confirmed by an X-ray analysis of the platinum(II) complex trans-[PtCl(CH3){2-PPh2C6H4NH(SO2C6H4CH(3-4)}2].     

The synthesis and characterization of a new (E,E)-dioxime and its mono and heterotrinuclear complexes containing dioxadithiadiazamacrobicyclic moieties

A new (E,E)-dioxime (2Z,3Z)-1,4,7,8,15,16-hexahydro-9,14-(ethanothioethanothioethano)quinoxalino[6,7-e] [4,7,1,10]benzodioxadiazacyclododecine-2,3,19,26-tetrone2,3-dioxime (H₂L) has been synthesized by reacting cyanogen-di-N-oxide with 2,3-diamino-6,7,14,15-tetrahydro-8,13-(ethanothioethanothioethano)dibenzo[b,h] [1,4,7,10]dioxadiazacyclodecine-17,24-dione (6). Mononuclear complexes (8, 9) of this ligand have been synthesized by reacting the vic-dioxime (H₂L) with NiCl₂ · 6H_2O and COCl₂ · 6H₂O respectively. The BF ₂ ⁺ capped cobalt(III) complex (10) of the new (E,E) vic-dioxime has been synthesized by using as precursor a hydrogen-bridged mononuclear cobalt(III) complex (9). The heterotrinuclear complex (11) has been prepared by reacting one mononuclear cobalt(III) complex (10) with [Cu(MeCN)₄]PF₆. The new compounds were characterized by a combination of elemental analysis, ¹H- and ¹³C-n.m.r, i.r. and m.s. spectral data.     

Oxidative group transfer to Co(I) affords a terminal Co(III) imido complex

The synthesis of the first terminal imido complex of cobalt, [PhBP3]CoN-p-tolyl, is reported. Its synthesis proceeds by oxidative group transfer from cobalt(I) upon addition of tolyl azide at room temperature. This species and a related eta1-diazoalkane adduct have been structurally characterized. The diamagnetic imido complex [PhBP3]CoN-p-tolyl reacts with CO to liberate isocyanate and the cobalt(I) dicarbonyl complex [PhBP3]Co(CO)2.     

Crystal structure of bis(2-(2-thiazolylazo)-4-methylphenol)cobalt(III)chloride.

The reaction between CoCl2 x 6H2O and 2-1-(2-thiazolylazo)-p-cresol (TAC) in acetone resulted in six coordinated cobalt(III) complex, [Co(TAC)2]Cl3. Two TAC ligands coordinate with cobalt ion forming four five membered chelate rings. The cobalt ion is octahedrally coordinated by a phenolic oxygen, azo nitrogen and nitrogen in thiazole rings. Three chloride ions are disordered.     

Synthesis, characterization, and chiral properties of CoIII2AgI3 pentanuclear, CoIII4ZnII4 octanuclear, and CoIII mononuclear complexes with aza-capped hexadentate-N3S3 thiolate ligands: crystal structures of

The reaction of an S-bridged Co2(III)Ag3(I) pentanuclear complex, [Ag3[Co(aet)3]2][BF4]3 (aet = NH2CH2CH2S-), with paraformaldehyde in basic acetonitrile, followed by adding aqueous ammonia, produced an aza-capped Co2(III)-Ag3(I) complex, [Ag3[Co(L)]2]3+ ([1]3+) (L = N(CH2NHCH2CH2S-)3). The crystal structure of [1]3+ was determined by X-ray crystallography. [1][PF6]3 x H2O, empirical formula C18H44Ag3Co2F18N8OP3S6, crystallizes in the tetragonal space group 142m with a = 13.012(1) A, c = 24.707(2) A, and Z = 4. In [1]3+ the two aza-capped [Co(L)] units are linked by three Ag(I) atoms, such that the two Co(III) atoms are encapsulated in a macrobicyclic metallocage, [Ag3(I)(L)2]3-. [1]3+ was converted to an aza-capped Co4(III)Zn4(II) octanuclear complex, [Zn4O[Co(L)]4]6+ ([2]6+), by reaction with I- in the presence of Zn2+ and ZnO in water. The crystal structure of [2]6+ was also determined by X-ray crystallography. [2][PF6]6 x 8H2O, empirical formula C36H100Co4F36N16O9P6S12Zn4, crystallizes in the monoclinic space group P2(1/n) with a = 14.33(7) A, b = 25.67(10) A, c = 24.83(6) A, beta = 101.3(3) degrees , and Z = 4. In [2]6+ each of four [Co(L)] units is bound to each trigonal Zn3(II) face of the tetrahedral [Zn4(II)O]6+ core, such that each Co(III) atom is encapsulated in a macrobicyclic [Zn4(II)O(L)] fragment. Treatment of [2]6+ with a basic aqueous solution resulted in a cleavage of the Zn-S bonds to produce an aza-capped Co(III) mononuclear complex, [Co(L)] ([3]), from which [1]3+ is readily reproduced by the reaction with Ag+ in water. All the reactions were found to proceed with retention of the absolute configuration (delta or lambda) of the Co(III) chiral centers; deltadelta-[1]3+, deltadeltadeltadelta-[2]6+, and A-[3] were derived from deltadelta-[Ag3[Co(aet)3]2]3+. The contributions to circular dichroism (CD) from the triple helicity in [1]3+, besides from the asymmetric N and S donor atoms and the Co(III) chiral centers in [1]3+ and [2]6+, were estimated by comparing the CD spectra of deltadelta-[1]3+, deltadeltadeltadelta-[2]6+, and delta-[3].     

Steric control of organic transformation by a dendrimer cage: organocobalt dendrimer porphyrins as novel coenzyme B(12) mimics

Cobalt(II) complexes of poly(aryl ester) dendrimer porphyrins (m-[Gn]TPP)Co(II) and (p-[Gn]TPP)Co(II) (n = 0-3) underwent AIBN-initiated alkylation (AIBN = 2,2'-azobis(isobutyronitrile)) at the metal center with propargyl alcohol in CDCl(3) at 60 degrees C, where the dendritic substituents did not affect the overall conversion rate but selectivity of the alkylation. With the largest (m-[G3]TPP)Co(II), a single organocobalt(III) species (Co(III)-C(=CH(2))CH(2)OH, 4) was selectively formed in 91% yield, due to a steric protection of 4 by the large dendrimer cage from the access of another molecule of cobalt porphyrin species. In contrast, with other cobalt(II) porphyrins, isomerized compounds such as Co(III)-C(CH(3))=CHOH (5) and Co(III)-CH(CH(3))CHO (6) were formed in addition to 4. A stereochemical investigation with (m-[G3]TPP)Co(II) using AIBN-d(12), in place of nondeuterated AIBN, demonstrated that the alkylation (cobalt(III) hydride addition to propargyl alcohol) is selective to a trans adduct. Results also indicated that this addition step does not involve external activation of propargyl alcohol.     

Synthese von Diaza-octahydroporphinato-kobalt (III)-Komplexen als Vitamin-B12-Modellverbindungen

Synthesis of Octahydro-porphinato-cobalt(III) Complexes as Vitamin B₁₂ Model Compounds The synthesis of (±)-dibromo[1-hydroxy-2,2,3,3,7,7,8,8,12,12,13,13,17,17,18,18-hexadecamethyl-10,20-diaza-octahydroporphinato]cobalt(III) (2a) is described. The dicyano complex 2b and the corresponding annulene complex 3 have been obtained by exchange of its axial ligands and by elimination of the hydroxy group, respectively.     

Mononuclear nickel(III) complexes [Ni(III)(OR)(P(C6H3-3-SiMe3-2-S)3)](-) (R = Me, Ph) containing the terminal alkoxide ligand: relevance to the nickel site of oxidized-form [NiFe] hydrogenases

The unprecedented nickel(III) thiolate [Ni (III)(OR)(P(C 6H 3-3-SiMe 3-2-S) 3)] (-) [R = Ph ( 1), Me ( 3)] containing the terminal Ni (III)-OR bond, characterized by UV-vis, electron paramagnetic resonance, cyclic voltammetry, and single-crystal X-ray diffraction, were isolated from the reaction of [Ni (III)(Cl)(P(C 6H 3-3-SiMe 3-2-S) 3)] (-) with 3 equiv of [Na][OPh] in tetrahydrofuran (THF)-CH 3CN and the reaction of complex 1 with 1 equiv of [Bu 4N][OMe] in THF-CH 3OH, respectively. Interestingly, the addition of complex 1 into the THF-CH 3OH solution of [Me 4N][OH] also yielded complex 3. In contrast to the inertness of complex [Ni (III)(Cl)(P(C 6H 3-3-SiMe 3-2-S) 3)] (-) toward 1 equiv of [Na][OPh], the addition of 1 equiv of [Na][OMe] into a THF-CH 3CN solution of [Ni (III)(Cl)(P(C 6H 3-3-SiMe 3-2-S) 3)] (-) yielded the known [Ni (III)(CH 2CN)(P(C 6H 3-3-SiMe 3-2-S) 3)] (-) ( 4). At 77 K, complexes 1 and 3 exhibit a rhombic signal with g values of 2.31, 2.09, and 2.00 and of 2.28, 2.04, and 2.00, respectively, the characteristic g values of the known trigonal-bipyramidal Ni (III) [Ni (III)(L)(P(C 6H 3-3-SiMe 3-2-S) 3)] (-) (L = SePh, SEt, Cl) complexes. Compared to complexes [Ni (III)(EPh)(P(C 6H 3-3-SiMe 3-2-S) 3)] (-) [E = S ( 2), Se] dominated by one intense absorption band at 592 and 590 nm, respectively, the electronic spectrum of complex 1 coordinated by the less electron-donating phenoxide ligand displays a red shift to 603 nm. In a comparison of the Ni (III)-OMe bond length of 1.885(2) A found in complex 3, the longer Ni (III)-OPh bond distance of 1.910(3) A found in complex 1 may be attributed to the absence of sigma and pi donation from the [OPh]-coordinated ligand to the Ni (III) center.     

Preparation,Spectroscopic Properties and Characterization of Oxovanadium(IV), Isothiocyanatomanganese(III), Cyanocobalt(III) and Cobalt(II) Complexes with a Bis-Crown Ether Tetraaza[14]Annulene

Oxovanadium(IV), isothiocyanatomanganese(III), cyanocobalt(III) and cobalt(II) complexes of tetraaza[14]annulene appended with two crown ethers at 2,3- and 11,12-positions have been prepared. Cation complexation behavior of these cavity-bearing tetraaza[14]annulene complexes has been investigated by optical absorption methods. The cation K + , which necessitates two crown ether cavities for complexation, induces dimerization of the tetraaza[14]annulene complexes, whereas the Na + does not. Formation of the sandwich complexes due to dimerization is hindered by the steric interactions involving the axial ligand as judged by the blue shift of the intense band around 385-425 nm. Judging from its ESR spectrum, the cobalt(II) complex becomes a monomeric dioxygen complex of a 1 : 1 molar ratio in the presence of O 2 and pyridine at 77 K.     

Structural characterization of a lanthanum bistriflimide complex, La(N(SO2CF3)2)3(H2O)3, and an investigation of La, Sm, and Eu electrochemistry in a room-temperature ionic liquid, [Me3N(n)Bu][N(SO2CF3)2

The reduction of selected lanthanide cations to the zerovalent state in the room-temperature ionic liquid [Me3N(n)Bu][TFSI] is reported (where TFSI = bistriflimide, [N(SO2CF3)2]-). The lanthanide cations were introduced to the melt as the TFSI hydrate complexes [Ln(TFSI)3(H2O)3] (where Ln = La(III), Sm(III) or Eu(III)). The lanthanum compound [La(TFSI)3(H2O)3] has been crystallographically characterized, revealing the first structurally characterized f-element TFSI complex. The lanthanide in all three complexes was shown to be reducible to the metallic state in [Me3N(n)Bu][TFSI]. For both the Eu and Sm complexes, reduction to the metallic state was achieved via divalent species, and there was an additional observation of the electrodeposition of Eu metal.     

Syntheses,Structures and Characterization of Cobalt(II) and Cobalt(III) Complexes with N-Benzylated Polyamines and a Terminal Azido Ligand

Mononuclear cobalt(II) and cobalt(III) complexes, [Co(trenb)(N₃)]Cl (1) and [Co(dienb)(N₃)₂(OAc)] (2) (trenb = tris[2-(benzylamino)ethyl]amine, dienb = 1,9-diphenyl-2,5,8-triazanonane) were synthesized and characterized by elemental analyses, IR and electronic spectra. Their crystal structures were also determined by X-ray diffraction analyses. In Complex 1, cobalt(II) is five-coordinate trigonal bipyramidal with one azido nitrogen atom and four nitrogen donors of the tripodal ligand; the chloride interacts weakly with one of the secondary amino groups of trenb via a hydrogen bond. In Complex 2, cobalt(III) is in a distorted octahedral coordination environment, consisting of three nitrogen atoms of the amine ligand, two azide nitrogen atoms and an oxygen atom of the acetate ion; a six-membered ring involving the hydrogen bond may stabilize the complex, which maintains its solid geometry in DMF as indicated by the electronic spectrum.     

Metal-driven ligand assembly in the synthesis of cyclodextrin [2] and [3]rotaxanes

Cyclodextrin [2] and [3]rotaxanes have been synthesised by use of a metal-driven ligand formation methodology. The kinetically stable cobalt(III) complexes formed act as either linking or capping groups, the function being selected by manipulation of the reaction conditions to promote the formation of either 2:1 or 1:1 complexes, respectively. In all cases, mixtures of isomers containing different alpha-cyclodextrin orientations were observed. All three orientational isomers of the [3]rotaxane were isolated and structurally characterized by 2D NMR.     

Novel copper(II) induced formation of a porphyrinogen derivative: X-ray structural,spectroscopic, and electrochemical studies of porphyrinogen complexes of Cu(II) and Co(III) complex of a trispyrazolyl tripodal ligand

Copper(II) complexes of a novel pyrazole containing porphyrinogen and cobalt(III) and zinc(II) complexes of a pyrazole containing tripodal ligand having N-donor atoms have been investigated. 5-Methyl-3-formylpyrazole (MPA) on reaction with copper(II) nitrate or perchlorate in the presence of tris(2-aminoethyl)amine (tren) forms novel pyrazole-based porphyrinogen complexes [Cu(T(3)-porphyrinogen)(H(2)O)](NO(3))(2) (1a) and [Cu(T(3)-porphyrinogen)(H(2)O)](ClO(4))(2) (1b) where T(3)-porphyrinogen is 1,6,11,16-tetraaza-5,10,15,20-tetrahydroxy-2,7,12,17-tetramethylporphyrinogen. The same products are also obtained when tren is replaced by triethylamine. By contrast, the reaction between MPA, tren, and cobalt(II) perchlorate produces the cobalt(III) complex [Co(HMPz(3)tren)]ClO(4) (2) derived from the tripodal Schiff base tris[4-(3-(5-methyl-pyrazolyl)-3-aza-3-butenyl]amine (H(3)MPz(3)tren). The X-ray crystal structures of the copper(II) complexes (1a and 1b) and the cobalt(III) complex (2) have been determined. The structures show distorted square pyramidal coordination environments for 1a and 1b with the water molecule occupying the apical site, while for complex 2 a distorted octahedral geometry is obtained. Data for 1a follow: a = 19.476(3) A, b = 9.4116(8) A, c = 14.204(3) A; alpha = 90 degrees = gamma, beta = 107.58(2) degrees; V = 2482.0(7) A(3), Z = 4. Data for 1b follow: a = 20.967(3) A, b = 9.1563(18) A, c = 14.858(4) A; alpha = 90 degrees = gamma, beta = 108.44(3) degrees; V = 2706.0(10) A(3), Z = 4. Data for 2 follow: a = 21.293(3) A, b = 12.724(2) A, c = 19.777(4) A; alpha = 90 degrees = gamma, beta = 93.03(2) degrees; V = 5350.6(15) A(3), Z = 8. All three complexes crystallize in the monoclinic crystal system with the C2/c space group. The complexes are further characterized by UV-vis, IR, EPR, and electrochemical studies.