Pd(0) and Pd(II) derivatives with heteroannularly bridged chiral ferrocenyl diphosphine ligands - A stereochemical analysis

The ligands (S_c, S_p)-1-diphenylphosphino-2,1′-(1-dicyclohexylphosphinopropanediyl)ferrocene, (S_c, S_p)-PP^CyPF, and (S_c, S_p)-1-diphenylphosphino-2,1′-(1-diphenylphosphinopropanediyl)ferrocene, (S_c, S_p)-PP^PhPF, have been used in the synthesis of the new Pd(0) and Pd(II) derivatives [Pd(PP^CyPF)(DMFU)] (1) (DMFU = dimethylfumarate), [Pd(PP^CyPF)(MA)] (2) (MA = maleic anhydride), [Pd(η³-2-Me-C₃H₄)(PP)]OTf (PP = PP^CyPF, 3; PP^PhPF, 4) (OTf = triflate), [PdRR′(PP)] (R = Me, R′ = Cl, PP = PP^CyPF, 5, PP^PhPF, 6; R = R′ = Me, PP = PP^CyPF, 7, PP^PhPF, 8; R = R′ = C₆F₅, PP = PP^CyPF, 9, PP^PhPF, 10). The molecular structure of 7 has been determined by X-ray diffraction. In the cases of complexes 1-4 two isomers are formed depending on the orientation of the ancillary ligand with respect to the ferrocenyl core. The stereochemistry of these complexes has been determined. In complex 6 the two possible isomers are obtained whereas in complex 5 the derivative with the Me group trans to PPh₂ is selectively formed. Restricted rotation of the pentafluorophenyl groups with respect to the Pd-C bond has been found in 9 and 10. In all derivatives the conformation of the ferrocenyl ligand is the same as that seen by X-ray diffraction and deduced from NMR data.     

Carbonylation of four-membered ruthenium and osmium metallacycles incorporating an orthometallated phenolic function: New acylruthenium and arylosmium complexes

The solution reaction of Ru(QL¹)(PPh₃)₂(CO)Cl (3) and Os(QL¹)(PPh₃)₂(CO)Br (4) with carbon monoxide at one atmosphere pressure has respectively afforded the orange acylruthenium system Ru(QL²)(PPh₃)₂(CO)Cl (5) and the yellow arylosmium dicarbonyl system Os(QL³)(PPh₃)₂(CO)₂Br (6) in excellent yields. (QL¹ is C₆H₂O-2-CHNHC₆H₄Q(p)-3-Me-5, QL² is C₆H₂(CO-1)O-2-CHNHC₆H₄Q(p)-3-Me-5 and QL³ is C₆H₂OH-2-CHNC₆H₄Q(p)-3-Me-5 and Q is Me, OMe and Cl.) It is proposed that in the case of 3 a dicarbonyl complex similar to 6 is formed as an intermediate which rapidly undergoes aryl migration with concomitant phenolato coordination furnishing 5. The stability of 6 is consistent with the greatly diminished ability of osmium in promotion of migratory reactions. In the reaction 4 → 6 the Os-O(phenolato) bond is cleaved and the Schiff base moiety undergoes iminium-phenolato → imine-phenol tautomerization. The observed cis geometry of 6 may arise by a concerted route involving edge displacement of the halide ligand. The crystal and molecular structure of 5(Q = Cl) has revealed the presence of a distorted octahedral RuC₂P₂OCl coordination sphere and a highly planar acyl chelate ring characterized by a Ru-C distance of 2.013(4) Å. In the hydrogen bonded zwitterionic iminium-phenolato ring the N ? O distance is 2.561(6) Å. The acyl complexes of type 5 display an MLCT band near 500 nm which is absent in 6. The Schiff base CN stretch in 5 (∼1630 cm⁻¹) is significantly higher than that in 6 (∼1600 cm⁻¹) which displays two strong CO stretches near 2020 and 1940 cm⁻¹ (cis-Os(CO)₂ configuration). A single ³¹P NMR signal occurs in both 5 and 6 near 37 and −6 ppm, respectively (trans-M(PPh₃)₂ configuration). The voltammetric reduction potentials of the M^III/M^II couple is observed near 1.0 and 0.8 V vs. SCE in 5 and 6, respectively. Both are significantly higher than those in parent complexes (3 and 4) due to stabilization of the bivalent state upon carbonylation.     

Synthesis and characterization of para-nitro substituted 2,6-bis(phenylimino)pyridyl Fe(II) and Co(II) complexes and their ethylene polymerization properties

Four iron(II) and cobalt(II) complexes ligated by 2,6-bis(4-nitro-2,6-R₂-phenylimino)pyridines, LMCl₂ (1: R = Me, M = Fe; 2: R = iPr, M = Fe; 3: R = Me, M = Co; 4: R = iPr, M = Co) have been synthesized and fully characterized, and their catalytic ethylene polymerization properties have been investigated. Among these complexes, the iron(II) pre-catalyst bearing the ortho-isopropyl groups (complex 2) exhibited higher activities and produced higher molecular weight polymers than the other complexes in the presence of methylaluminoxane (MAO). A comparison of 2 with the reference non-nitro-substituted catalyst (2,6-bis(2,6-diisopropylphenylimino)pyridyl)FeCl₂ (FeCat 5) revealed a modest increase of the catalytic activity and longer lifetime upon substitution of the para-positions with nitro groups (activity up to 6.0 × 10³ kg mol⁻¹ h⁻¹ bar⁻¹ for 2 and 4.8 × 10³ kg mol⁻¹ h⁻¹ bar⁻¹ for 5), converting ethylene to highly linear polyethylenes with a unimodal molecular weight distribution around 456.4 kg mol⁻¹. However, the iron(II) pre-catalyst 1 on changing from ortho-isopropyl to methyl groups displayed much lower activities (over an order of magnitude) than 2 under mild conditions. As expected, the cobalt analogues showed relatively low polymerization activities.     

Syntheses and crystal structures of azafulleroid and aziridinofullerene bearing silyl or germyl benzene

Addition of silyl and germylmethyl azides (1) to fullerene C₆₀ at 50 °C through [2+3] cycloaddition led to the formation of the triazoline adducts (2). Subsequently, heating 2 at 100 °C in the solid state, caused N₂ extrusion producing two different isomers, [5,6]-azafulleroid (3) and [6,6]-aziridinofullerene (4). The ¹³C NMR spectrum of 3 had an absence of resonances in the aliphatic region for the fullerene C₆₀ cage, showing a fulleroid with C_S symmetry. In contrast, 4 exhibited one sp³ resonance in the aliphatic region for the fullerene C₆₀ cage, indicative of an aziridinofullerene with C_2V symmetry. However, MALDI-TOF mass characterization was hampered because ion peaks corresponding to the bis-adduct are detected in positive ion mode measurements, whereas the ion peaks [M−N₂]⁻ for 2a as well as [M]⁻ for 3a and 4a are observed in negative ion measurements. In an effort to obtain X-ray data, silyl and germylphenyl groups were introduced to form intermolecular complexes with fullerene C₆₀. The X-ray structures of 3c and 3d revealed a strong enhancement of homoconjugation in the bridged annulene moiety based on POAV analysis. The X-ray structures of 3c,d and 4c were confirmed with the detection of silyl and germylphenyl-C₆₀ interactions, similar to dimethoxyphenyl-C₆₀ interactions.     

Synthesis of dinitrosyl iron complexes (DNICs) with intramolecular hydrogen bonding

HSCH₂CONHCH₃ and HSCH₂CON(CH₃)₂ containing a peptide bond are prepared for the synthesis of DNICs with/without intra-molecular hydrogen bonding, respectively. The IR ν(NO) bands of [(NO)₂Fe(SCH₂CONHCH₃)₂]⁻ (2) appears at 1751, 1700 cm⁻¹. In complex 2, the presence of intramolecular [NH?S] hydrogen bonding was verified by the observation of IR spectroscopy with N−H stretching frequency 3334 cm⁻¹ (CDCl₃) and subsequently confirmed by single-crystal X-ray diffraction showing N−S distance of 2.94 Å. Complex 2 displays the rhombic EPR spectrum with g₁ = 2.039, g₂ = 2.031 and g₃ = 2.013 at in frozen H₂O. Complexes 2 and 3 rapidly release NO when exposed to light. The time needed for photolysis reactions of 2 is two times faster than that of 3 in less polar solvent. Representative time courses for the photolability of 2 and 3 in THF display the NO-off ability: 2 > 3.     

Two near-UV and visible chromophores of CpCo(Dithiolene) complexes with pyridinium-dicyanomethylide group

Tetracyanoethylene oxide (TCNEO) reacted with [CpCo(dithiolene)] (Cp = η⁵-cyclopentadienyl) complexes having 4-pyridyl or 3-pyridyl group to undergo a dicyanomethylation to the nitrogen atom on the pyridyl group. The reaction of [CpCo(S₂C₂(⁴Py)₂)] (1) with TCNEO formed both the monodicyanomethylated [CpCo(S₂C₂(⁴Py)(⁴Py-C(CN)₂))] (1a) and bisdicyanomethylated [CpCo(S₂C₂(⁴Py-C(CN)₂)₂)] (1b). [CpCo(S₂C₂(²Py)(⁴Py))] (2) reacted with TCNEO to give [CpCo(S₂C₂(²Py)(⁴Py-C(CN)₂))] (2a) but no dicyanomethylation occurred on the 2-pyridyl group. 2 reacted with excess TCNEO to form the only dicyanomethylated acetylene derivative ²Py-CC-(⁴Py-C(CN)₂) (2c), followed by a dissociation of the CpCoS₂ fragment. The monodicyanomethylated [CpCo(S₂C₂(ⁿPy-C(CN)₂)(2-thienyl))] (n = 4 (4a) or 3 (5a)) complexes were also prepared from [CpCo(S₂C₂(ⁿPy)(2-thienyl))] (n = 4 (4) or 3 (5)) and TCNEO. 1b was structurally characterized by X-ray diffraction study. The all dicyanomethylated [CpCo(dithiolene)] complexes showed the dithiolene LMCT absorption in the range of 605-644 nm (ε = 7000-9200 M⁻¹ cm⁻¹) and very strong absorption due to their pyridinium-dicyanomethylide moieties in near-UV region (e.g. 1b: λ_max = 470 nm, ε = 43,400 M⁻¹ cm⁻¹). The CV of the all dicyanomethylated complexes exhibited two reduction waves. The first reduction is due to Co^III/Co^II and the second one is due to the reduction of the pyridinium-dicyanomethylide moiety. The reduced 1b⁻ is stable enough for several minutes according to the visible spectroelectrochemical measurement. The ESR spectrum of 1b⁻ indicated eight hyperfine splittings due only to the interaction with the nuclear spin of cobalt (I = 7/2).     

New interlocked molecules generated from a podand containing urea units and imidazolium salts using an anion template

A podand containing urea units (L) was found to form interlocked structures with 2,5-dihexylamide imidazolium salts (3·X), 2,5-dihexyl imidazolium salts (4·X), and 2,5-dihexyl benzoimidazolium salts (5·X), where X=Cl⁻, Br⁻, and PF₆⁻ using anions as templates. The binding ability of L and guest molecules was evaluated by ¹H NMR titrations in CDCl₃. It was found that L could form complexes with guest molecules in the following order, 3·X > 5·X > 4·X. Stabilities of the complexes also depended on shape of the templated anions: Cl⁻>Br⁻?PF₆⁻. Hydrogen bonding and π-π stacking interactions played an important role in the self-assembling of these interlocked molecules.     

Formations and electrochemical behavior of mononuclear and binuclear molybdenum dithiolene complexes with nitrosyl ligands: Evidence for the formation of a coordinatively unsaturated species [CpMo(NO)(dithiolene)]

The one-pot reaction of [Cp^∗Mo(NO)(CO)₂] with elemental sulfur and dimethyl acetylenedicarboxylate (C₂Z₂ (Z = COOMe)) gave the [2+2] cycloadduct of the mononuclear molybdenum dithiolene complex [Cp^∗Mo(NO)(S₂C₂Z₂)(C₂Z₂)] (1), and some binuclear complexes:[Cp^∗Mo(NO)(S₂C₂Z₂)]₂ (2), [Cp^∗₂Mo₂(NO)₂S₂(S₂C₂Z₂)] (3) and [Cp^∗Mo(NO)S₂]₂ (4).The reaction of [Cp^∗Mo(NO)(Cl)(μ-Cl)]₂ with OC{S₂C₂(COOMe)₂} in the presence of sodium methoxide also produced complex 2 and the paramagnetic Cp^∗Mo bisdithiolene complex [Cp^∗Mo(S₂C₂Z₂)₂] (5, Z = COOMe).The structures of complexes 1-5 were determined by X-ray crystal structure analysis.The nitrosyl ligands of complexes 1-4 showed a linear coordination to the molybdenum center (the Mo-N-O bond angles = 169-174°), and their N-O bond lengths were 1.17-1.20 Å.In the binuclear complexes 2-4, two nitrosyl ligands were placed at cis-position.Complexes 1 and 2 were characterized by cyclic voltammetry and spectroelectrochemistry (visible and IR). The electrochemical reduction of the dimeric complex 2 formed the monomeric dithiolene complex[Cp^∗Mo(NO)(S₂C₂Z₂)]⁻ (X⁻) whose lifetime was several minutes. When the anion X⁻ was electrochemically oxidized, the coordinatively unsaturated species X was generated, but it was immediately dimerized to afford the original dimeric complex 2. The reduction of the complex 1 included the elimination of the bridged DMAD moiety (C₂Z₂) to give the anion X⁻.     

Synthesis of bitetrathiafulvalenes with FeCl3-mediated homo-coupling of tetrathiafulvalenylmagnesium bromide and formation of nanostructures from bitetrathiafulvalenes having long alkylthio chains

The FeCl₃-mediated homo-coupling of 4,5-bis(alkylthio)-4′-tetrathiafulvalenylmagnesium bromide 5 produced the corresponding bitetrathiafulvalene derivatives 2a-d in moderate yields (25-51%). Bitetrathiafulvalenes 2c and 2d having long alkylthio chains formed nanostructures and showed bulk electric conductivities (σ_rt = 2.6 − 8.0 × 10⁻⁵ S cm⁻¹) in the neutral state owing to the fastener effect. Interestingly, the nanofiber of tetrakis(dodecylthio)bitetrathiafulvalene 2d exhibited a p-type semiconductivity as detected by AFM.     

Guanosine and fullerene derived de-aggregation of a new phthalocyanine-linked cytidine derivative

Electronic absorption and emission properties of a new cytidine tethered zinc phthalocyanine 2 were used to probe the aggregation and guanosine/C₆₀ derived de-aggregation of this nucleobase linked phthalocyanine. These experiments revealed that 2 aggregates even at low concentrations in a competitive solvent system (1.1×10⁻⁶ M in 20% DCM/toluene). Nucleobase-metal coordination and slipped co-facial π-stacking interactions are both important in aggregate formation. Guanosine 5, C₆₀6, and a guanosine-C₆₀ chimera 4 were employed as potential aggregate disruptors. These experiments revealed that both guanosine and fullerene subunits are effective in disrupting the aggregate formed by 2. Such findings support the conclusion that base-pairing, π-stacking, as well as nucleobase-metal coordination interactions play important roles in the de-aggregation of 2.     

Modulation of intermolecular exchange interaction in organic radical based compounds: Magneto-structural analysis of phenol and imidazolium substituted oxoverdazyl radicals

The synthesis of two oxoverdazyls based compounds, the 1,5-dimethyl-3-(2′-hydroxyphenyl)-6-oxoverdazyl 1 and the perchlorate salt of 1,5-dimethyl-3-(2′-imidazolium)-6-oxoverdazyl 2 are reported. The structural analysis of 1 reveals that radicals are closely packed in regular columns by way of π-stacking. In contrast, the packing in 2 is definitely influenced by the protonation state of the radical substituent and shows strong lateral staggering of the organic radicals. The organisation in the solid state strongly influences the intermolecular exchange interaction between π-stacked radicals which goes from J = −113 cm⁻¹ (H = −J∑S_iS_i+1) in 1 to J = −1.0 cm⁻¹ and J′ = −0.67 cm⁻¹ in 2.     

Synthesis and electrochemical properties of new cobalt and manganese phthalocyanine complexes tetra-substituted with 3,4-(methylendioxy)-phenoxy

The synthesis and electrochemical properties of new cobalt and manganese phthalocyanine complexes, tetra-substituted with 3,4-(methylendioxy)-phenoxy at the peripheral (complexes 3 and 5) and non-peripheral (complexes 4 and 6) positions, are reported. Complexes 3 and 4 showed Q-band absorption, in DMF, at 668 and 686 nm, respectively while Q-band due to complexes 5 and 6 appeared at 732 and 760 nm, respectively in CHCl₃. All the complexes showed well resolved redox processes attributed to both metal and ring based processes. Complexes 3 and 4 showed four redox processes, labeled I, II, III and IV. For complex 3, process I (Co^IPc⁻²/Co^IPc⁻³) was observed at −1.45 V, II (Co^IIPc⁻²/Co^IPc⁻²) at −0.38 V, III (Co^IIIPc⁻²/Co^IIPc⁻²) at +0.49 V and IV (Co^IIIPc⁻¹/Co^IIIPc⁻²) at +0.97 V versus Ag|AgCl. Similar processes were observed for complex 4 at −1.36 V, −0.27 V, +0.56 V, +1.03 V versus Ag|AgCl, respectively. Complexes 5 and 6 showed two redox processes (I and II). For complex 5, these processes appeared at −0.79 V (Mn^IIPc⁻²/Mn^IIPc⁻³, I) and −0.07 V versus Ag|AgCl (Mn^IIIPc⁻²/Mn^IIPc⁻², II), while for complex 6, they were observed at −0.86 V and −0.04 V versus Ag|AgCl. Spectroelectrochemistry was used to probe and confirm the origin of these processes.     

Pluri-dimensional hydrogen-bonded networks of novel thiophene-introduced oligo(imidazole)s and physical properties of their charge-transfer complexes with TCNQ

Novel π-extended oligo(imidazole)s composed of imidazole and thiophene ring systems, bis(imidazolyl)thiophenes 1-4, were synthesized as new building blocks for electron-donor molecules having diverse hydrogen-bonding directionalities in order to explore hydrogen-bonded charge-transfer complexes and supramolecular assemblies. The cyclic voltammetry of these compounds showed increase of electron-donating ability compared with those of 2,2′- and 4,4′-biimidazoles. In the crystal structure, 1, 2 and 3 exhibited multi-dimensional hydrogen-bonded networks via solvent molecules including the π-π interaction. Charge-transfer complexes of 1, 2 and 4 with TCNQ were characterized as partial charge-transfer complexes with segregated stacks. The compressed pellets of the TCNQ complex of 2 showed a high electrical conductivity (σ_rt=5.2×10⁻² S cm⁻¹) at room temperature with semiconducting behavior (activation energy, E_a=71 meV).     

Synthesis and characterization of α,ω-disubstituted quaterthiophenes functionalized with polar groups for solution processed OTFTs

A series of soluble quaterthiophenes (4Ta-g) bearing ester groups in the α,ω-terminal positions separated from the quaterthiophene core by ethylene (4Ta-c), vinylene (4Td-f) or ethynylene (4Tg) spacers was synthesized by means of a Pd-catalyzed homocoupling of bithiophenes proceeding via C-H bond activation. The synthetic approach gave satisfying yields of 4Ta-f but resulted in only 3% yield of 4Tg due to the competitive hydrofluorination of the triple bond. The quaterthiophenes 4Ta-g were characterized by NMR, FTIR, UV-vis, PL spectroscopies, HRMS, TGA and CV. Thin-films of 4Ta-g were deposited either by spin-coating or by thermal evaporation on Si/SiO₂ for the fabrication of top-contact OTFTs. The devices prepared using 4Ta-c bearing the ester functional group separated from the quaterthiophene core by an ethylene spacer showed average hole field-effect mobility up to 2.7×10⁻³ cm² V⁻¹ s⁻¹ and up to 6×10⁻³ cm² V⁻¹ s⁻¹ for solution processed and for thermally evaporated OTFTs, respectively. The remarkably high solubility of 4Ta-c, along with their respectable performances in OTFTs render these molecules promising for practical applications as active layers in chemically-sensitive devices.     

Solvatochromism, hyperpolarizability, molecular and crystal structure of betaine dye 4-(2,4,6-triphenylpyridinium-1-yl)-phenolate

Solvatochromic effect of 4-(2,4,6-triphenylpyridinium-1-yl)-phenolate hydrate, 1, was determined. CT absorption band, which gave the shift from 23,880 (in water solution) to 14,440 cm⁻¹ (in anisole solution) allowed the molecular second order polarizability β_CT to be estimated as 59.5×10⁻³⁰ cm⁵ esu⁻¹. The crystal structure of 1 was determined: C₂₉H₂₁NO·5.78H₂O; orthorhombic, C222₁, a=15.005(9), b=24.356(4), c=7.5097(9) Å; V=2744.5(17) Å³, Z=4, D_X=1.224 g cm⁻¹; λ=0.71073 Å (Mo Kα); μ=0.087 mm⁻¹; final R₁=0.0551 for 2882 reflections [I>2σ(I)]. The molecules of 1, in an anti-parallel arrangement, form columns along the c-axis through stacking between the pyridinium ring and a phenyl ring in para position of the neighbouring molecule. Water molecules filling channels between the columns are disordered. Two of water molecules are connected by hydrogen bonds with negatively charged oxygen atom of 1. Powdered samples of 1 revealed only weak SHG response as measured using HRS method in relation to urea standard.     

Two new coordination polymers of Robson-type macrocycle bridged by perchlorate anions: Structure,electrochemistry and magnetism

Two new coordination polymers of Robson-type macrocycles, [Cu₂L¹(μ-ClO₄)₂]_∞ (1) and [Cu₂L²(μ-ClO₄)₂]_∞ (2) (where H₂L¹and H₂L² are the [2+2] condensation products of 2,6-diformyl-4-flurophenol with 1,3-diaminopropane and 2-hydroxy-1,3-diaminopropane, respectively), have been synthesized and characterized. The intriguing feature is that intermolecular perchlorato bridges occur between adjacent copper(II) centers. The cyclic voltammograms of the complexes show that each complex undergoes two pseudo-reversible processes with the half wave potentials, −0.361 V and −0.729 V for 1, and −0.372 V and −0.744 V for 2, respectively. Magnetic susceptibility was measured for 1 and 2 over a temperature range of 2–300 K. The optimized magnetic data were J = −359.6 cm⁻¹, j′ = −30 cm⁻¹ and R = 6.8 × 10⁻⁸ for 1 and J = −411 cm⁻¹, j′ = −26 cm⁻¹ and R = 2.4 × 10⁻⁷ for 2, respectively. The data reveal antiferromagnetic couplings between the copper(II) ions of intra- and intermolecular units.     

Heavy analogues of the 6π-electron anionic ring systems: Cyclopentadienide ion and cyclobutadiene dianion

The heavy analogues of the anionic 6π-electron systems, lithium 1,2-disila-3-germacyclopentadienide 2⁻ · [Li⁺(thf)], 1,2-disila-3,4-digerma- and 1,2,3,4-tetrasilacyclobutadiene dianions 7²⁻ · 2[K⁺(thf)₂] and 8²⁻ · 2[K⁺(thf)₂], were synthesized by the reduction of the neutral precursors 1, 3 and 4, respectively. 2⁻ · [Li⁺(thf)], the heavy analogue of the cyclopentadienide ion, is an aromatic compound, whereas 7²⁻ · 2[K⁺(thf)₂] and 8²⁻ · 2[K⁺(thf)₂], the heavy analogues of the cyclobutadiene dianion, are both non-aromatic.     

(Cyclopentadienyl)chromiumtricarbonyl dimers as a source of metal-centered free-radicals to form stable η-bonded spin-adducts with fullerenes

Spin-adducts (I, IIb-c) of C₆₀ and C₇₀ with metal-centered free radicals CpCr(CO)₃ (I, IIa) have been generated in toluene via interaction between fullerenes and the weakly metal-metal bonded dimeric complexes [CpCr(CO)₃]₂ (Cp = η⁵-C₅H₅ (I); Cp = η⁵-C₅Me₅ (II)). Their structures have been investigated using ESR spectroscopy and DFT-PBE calculations and η²-bonding to the CC bond between two hexagons in C₆₀ has been established. Calculations have been extended to investigate the nature of the intermediate η²-coordinated toluene chromium complexes (I, IId).     

Three-dimensional acentric coordination polymers formed from the linkage of cobalt and nickel malonate quadratic layers through a kinked organodiimine: Synthesis,structure, thermal properties and magnetochemistry

Hydrothermal synthesis has afforded a pair of isostructural acentric three-dimensional coordination polymers {[M₂(malonate)₂(dpa)(H₂O)₂] · 2H₂O}_n (M = Co, 1; M = Ni, 2; dpa = 4,4′-dipyridylamine), which were structurally characterized via single-crystal X-ray diffraction and spectroscopically and thermally analyzed. Both materials exhibit exotridentate malonate ligands conjoining metal atoms into grid-like [M(malonate)(H₂O)]_n layers; in turn, these are connected into 3-D sqp lattices (4⁴6⁶ topology) through tethering dpa ligands. The central kink and inter-ring torsion within the dpa ligands enforces the acentric Aba2 space group of crystals of 1 and 2. Antiferromagnetic coupling (g = 2.08(2), J = –1.05(8) cm⁻³) was observed within the malonate-bridged layer motifs within the cobalt derivative 1. In contrast, the nickel congener 2 exhibited ferromagnetic coupling (g = 2.201(1), J = 0.289(1) cm⁻³).