X-Ray Crystal Structure and Photo Chemistry of N-Methyl-N-(1-phenylvinyl)benzamide

Abstract  

N-methyl-N-(1-phenylvinyl)benzamide (I) has empirical formula C₁₆H₁₅NO, crystallizes in the monoclinic space group, P21/n, with unit cell parameters a = 8.9101(2) ?, b = 15.1416(4) ?, c = 9.7737(2) ?, α = 90°, β = 109.3320(10)°, γ = 90°, Z = 4. Interestingly, the Compound (I) undergoes photocyclization upon irradiation of light to give two cyclic lactams (A and B) below 3100 ?. Compound (I) can be cyclized at either of two equivalent ortho positions. The mechanism for formation of lactam A may involve electrocyclic ring closure reaction upon irradiation of light to give six-membered cyclic zwitterionic intermediate. The ring proton rearranges via [1, 5]-H shift to give isomerized product A. The minor photoproduct B is supposed to be formed via photocyclization process followed by a loss of proton and the tautomerized product undergoes oxidation for the revival of aromaticity.     

Synthetic and structural studies of the trans bis(2-N-H-pyrrolylcarbaldimine) complexes of nickel(II) and palladium(II)

The molecular bis(2-N-H-pyrrolylcarbaldimine)nickel(II) and palladium(II) complexes are isolated in moderate yield (30–35%) from in situ assembly of the Schiff base with metal(II) salt, base, and pyrrole-2-carbaldehyde in aqueous ammonia solution. The nickel(II) complex, 1, is monoclinic, space group P2₁/c, with a=11.289(6) ?, b=5.611(3) ?, c=8.287(5) ?, β=111.620(6)°, and V=488.0(5) ?³ with Z=2, for d _calc=1.667 Mg/m³. The palladium analog, 2, is isomorphous, space group P2₁/c, with a=11.481(3) ?, b=5.5738(10) ?, c=8.276(2) ?, β=110.923(12)°, and V=494.7(2) ?³ with Z=2, for d _calc=1.965 Mg/m³. In both crystal structures, the metal resides on an inversion center. In the IR spectra, ν(C=N) appears at 1561 cm⁻¹ in 1, and 1557 cm⁻¹ in 2, while ν(N–H) shows at 3345 cm⁻¹ and 3335 cm⁻¹, respectively. The ¹H-nmr spectra reveal the C–H and N–H protons of the imine group as sharp and broad doublets, respectively, at 7.62 and 8.38 δ in 1 and at 7.92 and 9.73 δ in 2.     

Synthesis,Crystal Structure and DNA Binding Property of Diaquadi(4-methylbenzoyloxy)bis[2-(4-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide]cobalt(II)

Abstract  

A novel cobalt(II) complex of [Co(4-MePhCOO)₂(NITpPy)₂(H₂O)₂] (1), where NITpPy is short for 2-(4-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxy 3-oxide(C₁₂H₁₆N₃O₂), was synthesized and structurally characterized by X-ray diffraction analysis. The X-ray diffraction analysis reveals that 1 crystallizes in the triclinic space group P-1 with a = 6.7910(10) ?, b = 12.4421(15) ?, c = 12.9169(16) ?, α = 89.8470(10)°, β = 89.8480(10)°, γ = 76.991(2)°, and Z = 1. The Co atom in the complex is located on the center of inversion and lies in a distorted octahedral geometry defined by an N₂O₄ donor set. The interaction of 1 with calf thymus DNA (CT-DNA) was investigated by UV–vis absorption and emission spectroscopy, which indicating that 1 could bind to DNA through electrostatic interaction.     

Molecular Structure of an Unexpected Binuclear Salicylaldimine Semicarbazone Palladium(II) Complex

Abstract  

Reaction of a salicylaldehyde semicarbazone ligand with PdCl₂(PPh₃)₂ yields an unexpected binuclear Pd(II) complex, 2. The complex crystallizes in a triclinic system with a P-1 space group, with unit cell parameters a = 14.0283(3) ?, b = 15.2603(3) ?, c = 18.7142(3) ?, α = 66.662(10)°, β = 86.162(10)°, γ = 76.265(10)°, Z = 2. The semicarbazone ligand acts as a tridentate chelating donor to one palladium metal centre, forming a five- and six- membered ring, and a monodentate donor to the second palladium centre. There are four molecules of solvent per complex molecule in the asymmetric unit. Each metal centre is contained within a slightly distorted square-planar environment.     

Structures of Two (<Emphasis Type="Italic">E</Emphasis>)-3-Substituted Cinnamoylbenzotriazole 1-Oxides

Abstract  

The molecule of (E)-3-(3-MeOC₆H₄CH=CHCO)-benzotriazole 1-oxide, 2, has a very near planar structure, while the 2-nitrophenyl ring is rotated out of the plane of the remaining atoms in (E)-3-(2-O₂NC₆H₄CH=CHCO)-benzotriazole 1-oxide, 1. The nitrogen oxide bond lengths in 1 and 2 are 1.258 (6) and 1.2683 (15) ?, respectively, and are in the region found for related compounds. There are no strong intermolecular hydrogen-bonds in either compound, instead there are weak C–H···O intermolecular hydrogen-bonds and π···π stacking interactions in 1, and C–H···O, C–H···π, and π···π stacking interactions in 2. Different three-dimensional arrays are generated in each case. Compound 1 crystallises in the orthorhombic space group Pna2₁, with a = 25.061 (2) ?, b = 3.6997 (2) ?, c = 14.2623 (12) ? and Z = 4. Compound 2 crystallises in the triclinic space group P-1, with a = 5.7297 (3) ?, b = 10.8440 (6) ?, c = 11.4965 (6) ?, α = 89.689 (3)°, β = 76.019 (3)°, γ = 75.047 (3)°, Z = 2.     

Synthesis and Crystal Structures of pH-Dependent Ni(II) Coordination Polymers with 3-Pyrid-3-ylbenzoic Acid

Abstract  

Two pyridinecarboxylato-bridged coordination polymers[Ni(pbc)₂(H₂O)₂]_n(1) and {[Ni(pbc) ₂ (H₂O)]·H₂O}_n (2)(Hpbc = 3-Pyrid-3-ylbenzoic acid) have been synthesized by the hydrothermal method and characterized by elemental analysis, IR spectrum and single crystal X-ray diffraction. Compound 1 crystallizes in monoclinic, space group P2₁/c with a = 9.519(5) ?, b = 9.417(5) ?, c = 11.701?, β = 98.086(5)°, V = 1038.5(9) ?³, Z = 2. Compound 2 crystallizes in monoclinic, space group P2₁/c with a = 10.490(2) ?, b = 12.920(3) ?, c = 16.074?, β = 95.97(3)°, V = 2166.7(8) ?³, Z = 4. X-ray diffraction analysis reveals that all pbc⁻ ligands act as diconnectors to link two Ni(II) centers and adopt one coordination mode: μ₂−N, O in compound 1 and the ligands adopt two coordination modes: μ ₂ −N, O and μ ₃ − N, O, O in compound 2.     

Synthesis and Crystal Structures of 4-(3-Nitropyridin-2-ylamino)phenol and 4-(3-Aminopyridin-2-ylamino)phenol

Abstract  

The title compounds, 4-(3-nitropyridin-2-ylamino)phenol (I) and 4-(3-aminopyridin-2-ylamino)phenol (II), are two intermediates for the synthesis of a potential antitumor agent ABT-751. The reaction of 4-aminophenol with 2-chloro-3-nitropyridine yielded I which was converted into II by reduction. Instead of the Pd/C catalytic hydrogenation described in many literature, reduction with cheap sodium sulfide in aqueous media was utilized for shorting the reaction time and simplifying the operation. The crystal structures of the resultant compounds were determined by single-crystal X-ray diffraction. The compound I is crystallized in P2₁/c space group of monoclinic system, with a = 11.5236(19) ?, b = 8.7389(17) ?, c = 10.684(3) ? and α = 90.00°, β = 107.76(3)°, γ = 90.00°. The compound II is crystallized in Cc space group of monoclinic system, with a = 10.688(2) ?, b = 14.2181(18) ?, c = 7.9836(15) ? and α = 90.00°, β = 125.801(7)°, γ = 90.00°. In both crystal structures, the intermolecular N–H–O and O–H–N hydrogen bonds link the molecules, which effectively stabilize the structures.     

Three-Six-Membered Rings with Diverse Conformations in the Structure of 9-(4-Methoxyphenyl)-3,3-Dimethyl-10-(4-Methylphenyl)-1,2,3,4,5,6,7,8,9,10-Decahydroacridin-1,8-Dione

Abstract  

The crystal structure of 9-(4-methoxyphenyl)-3,3-dimethyl-10-(4-methylphenyl)-1,2,3,4,5,6,7,8,9,10- decahydroacridin-1,8-dione is determined by X-ray diffraction at 153(2) K. The title compound 1, C₂₂H₂₁N₅O₆, is triclinic, space group P-1, a = 9.6382(15) ?, b = 11.5847(15) ?, c = 12.4722(11) ?, α = 66.075(9)°, β = 70.176(9)°, γ = 85.800(13)°, Z = 2, V = 1194.1(3) ?³. It is interesting that the central pyridine ring of the acridine moiety is slightly distorted and adopts a boat conformation. The outer six-membered ring with two methyl groups adopts half-chair conformation, while another outer partially saturated six-membered ring adopts distorted boat form. In addition, the un-classical hydrogen bonds of C–H···O link the molecules forming polymers in the crystals.     

Structures of Bis(1-ethylbenzimidazol-2-yl)alkyl Copper(II) Dichlorides: An Unusual Cocrystallization

Abstract  Two structures containing pseudo-tetrahedral Cu(II)N₂Cl₂ coordination complexes are reported. The first molecular structure (A) of the compound, 1,1′bis(1-ethylbenzimidazol-2-yl)propane copper(II) dichloride (triEtBBIM)Cu(II)Cl₂, 1, is reported. The complex crystallized in the triclinic space group P-1 with a = 8.616(3) ?, b = 9.302(3) ?, c = 14.314(4) ?, α = 85.613(6)°, β = 85.170(6)°, γ = 66.117(6)° and V = 1044.1(5) ?³ with Z = 2. The second structure (B) contains 1 and (3,3′bis(1-ethylbenzimidazol-2-yl)pentane) copper(II) dichloride (tetEtBBIM)Cu(II)Cl₂, 2, both of which, cocrystallize in an equal molar ratio with a nitromethane solvate molecule. The complex crystallized in the monoclinic space group P2₁/c with a = 18.876(4) ?, b = 14.975(3) ?, c = 18.344(4) ?, β = 116.75(3)°, and V = 4630.3(16) ?³ with Z = 4. The cocrystallization of such discrete complexes has been coined a chemical Janus. Graphical Abstract  The title complexes contain pseudo-tetrahedral Cu(II)N₂Cl₂ coordination. One of the structures is the result of an unusual cocrystallization, in which two different discrete Cu(II) molecules cocrystallize in an equimolar ratio with a nitromethane solvate molecule.      

The Synthesis and Crystal Structure Determination of Phenyl 2-(3,4-dihydro-1(2<Emphasis Type="Italic">H</Emphasis>)naphthalenylidine)hydrazinecarboxylate and Phenyl (2,4-dichlorophenyl-methylene)hydrazinecarboxylate

Abstract  

(E)-Phenyl 2-(3,4-dihydro-1(2H)-naphthalenylidine)hydrazinecarboxylate and (E)-phenyl (2,4-dichlorophenylmethylene)hydrazinecarboxylate were prepared by the condensation of 1-tetralone or 2,4-dichlorobenzaldehyde with phenyl hydrazinecarboxylate. Crystals of C₁₇H₁₆N₂O₂ 3 are monoclinic, C2/c, a = 17.763(4) ?, b = 8.353(2) ?, c = 40.233(8) ?, Z = 16, V = 5,839(2) ?³, R ₁ = 0.0448 and wR ₂ = 0.1104 for reflections with I > 2σ(I). Crystals of C₁₄H₁₀N₂O₂Cl₂ 5 are orthorhombic, P2₁2₁2₁, a = 8.288(3) ?, b = 14.082(2) ?, c = 23.788(5) ?, Z = 8, V = 2,777(1) ?³, R ₁ = 0.0815 and wR ₂ = 0.2006 for reflections with I > 2σ(I). The molecular packing in the crystal for both compounds is the result of N–H···O hydrogen bonding.     

Histamine Molecule and Dianion Oxalate are Efficient Blocks for Building 2D Supramolecular Networks

Abstract  

One salt and two Cu(II) complexes (H₂hsm)(ox), 1, [Cu(hsm)(ox)], 2, and [Cu(hsm)(ox)H₂O], 3, have been synthesized and X-ray characterized (hsm is histamine and ox²⁻ is the oxalate dianion). Starting from the prochiral tetracoordinated complex 2, pentacoordinated complex 3 crystallizes as a racemic mixture of the enantiomeric Δ and Λ isomers, in space group P2₁/c. In all cases, the side chain of the hsm group is gauche, allowing the formation of strong hydrogen bonds in the salt 1, and to chelate the metal center in complexes 2 and 3. The combination hsm/ox seems to favor the formation of 2D supramolecular structures (planes or wavy planes), through efficient networks of N–H···O hydrogen bonds. Cell parameters: 1, P2₁/c, a = 6.260 (2) ?, b = 11.500 (4) ?, c = 12.525 (4) ?, β = 104.047 (17)o; 2, C2/c, a = 10.7966 (13) ?, b = 15.5622 (16) ?, c = 11.3996 (15) ?, β = 106.261 (11)o; 3, P2₁/c, a = 7.0627 (6) ?, b = 7.1323 (6) ?, c = 20.0296 (19) ?, β = 91.529 (7)o.     

Coordination of 4-Aminoantipyrine to Rhenium(V)

Abstract  

The reactions of trans-[ReOX₃(PPh₃)₂] (X = Cl, Br) with 4-aminoantipyrine (H₂pap) were studied, and the complexes cis-[ReX₂(pap)(H₂pap)(PPh₃)](ReO₄) (X = Cl (1), Br (2)) were isolated. The crystal structure of 2 was determined by single-crystal X-ray diffraction. It crystallizes in the monoclinic space group P2₁ with a = 11.5145(6) ?, b = 11.5330(5) ?, c = 17.5492(9) ?, β = 105.322(2)°, V = 2247.6(2) ?³, Z = 2, C₄₀H₃₉N₆O₆PBr₂Re₂, M _r = 1262.97, D _c = 1.866 g cm⁻³, F(000) = 1208 and μ(Mo K _α) = 7.244 mm⁻¹, the final R = 0.0545 and wR = 0.1314. The ligand pap is coordinated through the doubly deprotonated amino nitrogen as an imide, and H₂pap acts as a neutral bidentate chelate, with coordination through the neutral amino nitrogen and the ketonic oxygen.     

Crystal Structure of Bis[hydrobis(3-phenylpyrazolyl)(5-phenylpyrazolyl)borato]-zinc(II)

Abstract  

The X-ray crystal structure of (C₅₄ H₄₂ B₂ N₁₂ Zn)*2(C H Cl₃) is reported. The title compound is a chloroform-solvated neutral complex crystallizing in the Triclinic space group, P − 1, with two half complexes (each located on a crystallographic center of inversion) and two full chloroform molecules appearing in the asymmetric unit. The capping ligands are related by symmetry and together form, essentially, an octahedral coordination sphere. Strain is apparent in the complex as indicated by asymmetric bond distances and angles. Final statistical data: R = 4.60% with I > 2σ(I), a = 11.2912(8) ?, b = 14.7912(11) ?, c = 17.0047(13) ?, α = 72.3560(10)°, β = 89.8950(10)°, γ = 88.1010(10)°, Z = 2.     

Synthesis and Crystal Structure of a New Cobalt(II) Complex: Bis(pyridine)bis(4,4,4-trifluoro-1-(6-methoxynaphthalen-2-yl)butane-1,3-dione) Cobalt(II)

Abstract  

A new Co(II) complex 2 with ligand 4,4,4-trifluoro-1-(6-methoxynaphthalen-2-yl) butane-1,3-dione 1 and pyridine are prepared and crystallized from an acetone solution. The obtained red and transparent crystal conforms to the empirical formula of Co(C₁₅H₁₀O₃F₃)₂·(C₅H₅N)₂. It crystallizes in monoclinic, space group C2/c with a = 23.3152(14), b = 12.0225(7), c = 15.3950(10) ?, β = 124.1360(10)°, V = 3571.8(4) ?³, Z = 4, C₄₀H₃₀CoF₆N₂O₆, Mr = 807.59, F(000) = 1652, Dc = 1.502 g/cm³, μ = 0.564 mm⁻¹, the final R = 0.0466 and wR = 0.1043 for 3901 observed reflections with I > 2σ(I). X-ray structural analysis revealed that the Co(II) atom is coordinated by two oxygen atoms of 1,3-dione ligands 1 and two nitrogen atoms of pyridines, forming a distorted octahedron coordination geometry.     

Synthesis,Spectroscopic Studies and X-ray Analysis of (<Emphasis Type="Italic">E</Emphasis>)-2-(2-Fluorophenyl)-3-(6-Nitrobenzo[d][1,3]dioxol-5-yl) Acrylic Acid

Abstract  

In the solid-state structure of the title compound, C₁₆H₁₀FNO₆, the configuration about the C=C double bond is E. The compound crystallized in the triclinic system, having space group P-1 with unit cell dimensions a = 5.829(10) ?, b = 8.801(16) ?, c = 13.543(3) ?, α = 87.753(15)°, β = 81.945(15)°, γ = 86.342(14)°. The structure of the molecule is V-shaped and in the crystal the molecules are linked to form inversion dimers connected by pairs of C–H···O hydrogen bonds.     

Group 6 metal carbonyl complexes of a bulky phosphine: The crystal structures of tris(trimethylsilyl)phosphine-M(0)pentacarbonyl, M = chromium, molybdenum, and tungsten

The crystal structures of M(P{Si(CH₃)₃}₃)(CO)₅, M = Cr (1), Mo (2), and W (3), have been determined. Crystal data for 1, trigonal crystal system, space group = P3₁, a, b = 9.2118(6) ?, c = 22.416(3) ?, V = 1647.3(2) ?³, Z = 3; for 2, trigonal crystal system, space group = P3₂, a, b = 9.3394(3) ?, c = 22.7375(12) ?, V = 1717.56(12) ?³, Z = 3; trigonal crystal system, space group = P3₂, a, b = 9.3147(5) ?, c = 22.6955(16) ?, V = 1705.33(18) ?³, Z = 3. All three structures show distorted octahedral coordination environments around the metal center and exhibit especially long M–P bond distances, illustrating the unique steric and electronic properties of this bulky phosphine ligand. The ³¹P{¹H} NMR spectra of the compounds are also reported.     

Orthorhombic Polymorphs of 1-Phenyl-3-(3-Hydroxyphenyl)-2-Propen-1-One

Abstract  

Chalcones, 1,3-diphenyl-2-propene-1-ones, exist naturally and synthetically, and are characterized by the linkage of two aromatic rings joining a three carbon α-β-unsaturated carbonyl entity. We report the observation of two new polymorphs of a hydroxy chalcone, C₆H₅–CO–CH=CH–C₆H₄ (m-OH), identified as a result of a Claisen–Schmidt synthesis and manual screening technique. One polymorph of this compound has been reported previously and exists in the monoclinic system, space group P2/n, with unit cell parameters a = 13.295(6) ?, b = 5.659(2) ?, c = 16.144(8) ?, β = 109.73(5)°, V = 1143.3(9) ?³, and Z = 4. Two crystalline forms (II and III) reported herein, are polymorphs of the reported monoclinic form (I). Form II exists in the orthorhombic system, space group Pca2₁, with unit cell constants a = 11.631 (2) ?, b = 13.163 (3) ?, c = 7.3977 (14) ?, V = 1132.6 (4) ?³, and Z = 4. Form III also crystallizes in the orthorhombic system, however in space group Pbca, with unit cell parameters a = 11.8100(8) ?, b = 7.4075(5) ?, c = 25.8729(19) ?, V = 2263.4(3) ?³, and Z = 8. Variations in the hydrogen bonding connectivity help to distinguish these two forms from the monoclinic, whereas crystal packing differentiates the two orthorhombic forms. The conformation of the C=C (C2–C3) is E for both orthorhombic forms.     

Hydrogen Bonded 3D Supramolecular Architectures of Three Saccharinate Salts

Abstract  

Three saccharinate salts (2-aminopyrimidine): (saccharin) (1), (4-phenylthiazol-2-amine): (saccharin) (2), and (2-methylquinoline): (saccharin) (3) were prepared and structurally characterized by X-ray crystallography. Salt 1 crystallizes in the monoclinic, space group P2(1)/c, with a = 7.1782(9) ?, b = 13.5105(16) ?, c = 12.2251(12) ?, β = 93.3410(10)°, V = 1183.6(2) ?³, Z = 4. Compound 2 crystallizes in the triclinic, space group P-1, with a = 7.4584(7) ?, b = 8.6930(9) ?, c = 12.9179(14) ?, α = 108.952(2)°, β = 91.7510(10)°, γ = 97.2280(10)°, V = 783.57(14) ?³, Z = 2. Compound 3 crystallizes in the monoclinic, space group P2(1)/c, with a = 7.781(8) ?, b = 19.4209(19) ?, c = 10.9719(12) ?, β = 107.7390(10)°, V = 1579.2(16) ?³, Z = 4. The different hydrogen bonding interaction modes of the saccharinate anions and the cations lead to 3D network structure, 3D staircase structure, and 3D ABAB layer structure for 1, 2, and 3 respectively. Despite variations in the cation shape on the aromatic N–heterocyclic compounds, there all existed strong intermolecular N–H⋯O(carbonyl) hydrogen bonds. In compounds 1, and 3 the N⁺–H⋯O interaction between the N⁺–H group of the cation and the C=O group of the saccharinate anion is the most important interaction in this family of salts. However, in 2, there was a N–H⋯O interaction between the amino proton and the C=O group of the saccharinate anion. At the next level, the aromatic C–H proton interacts with the sulfonyl O atom. There are also π–π interactions in compounds 1–2, there is CH₃–π interaction in 3. Under these interactions the three compounds exhibit synthons I–III respectively. These interactions are responsible for the high-yielding supramolecular assembly of N-containing aromatic bases and the saccharinate into salts.     

Ligand Substitution Chemistry of the Diphosphine Ligand endo,endo-2,3-Bis(diphenylphosphinomethyl)-5-norbornene (dpmn): Syntheses and X-ray Diffraction Structures of PtCl2(dmn) and PtMe2(dpmn)

Abstract  The reaction of phosphine ligand endo,endo-2,3-bis(diphenylphosphinomethyl)-5-norbornene (dpmn) with PtCl₂(cod) and PtMe₂(cod) yields PtCl₂(dpmn) (2) and PtMe₂(dpmn) (4), respectively. Treatment of 2 with excess MeLi or MeMgCl also furnishes 4 in good yield. Both new platinum compounds have been isolated and characterized by NMR spectroscopy (¹H and ³¹P), elemental analyses, and X-ray crystallography. 2 Crystallizes, as the CH₂Cl₂ solvate, in the orthorhombic space group Pnma, a = 18.062(3) ?, b = 16.602(3) ?, c = 11.088(2) ?, V = 3,324.7(9) ?³, Z = 4, D _cacl = 1.681 mg/m³; R = 0.0432, R _w = 0.0759 for 3,755 observed reflections with I > 2σ(I). 4 Crystallizes, as the CH₂Cl₂ solvate, in the orthorhombic space group Pnma, a = 17.969(3) ?, b = 16.689(3) ?, c = 11.237(2) ?, V = 3,370(1) ?³, Z = 4, D _cacl = 1.610 mg/m³; R = 0.0268, R _w = 0.0665 for 4,098 observed reflections with I > 2σ(I). The solid-state structures of 2 and 4 confirm the coordination of the platinum(II) center by the seven-membered chelating dpmn ligand; 2 and 4 represent the first structurally characterized examples of organometallic compounds based on the endo,endo-2,3-bis(diphenylphosphinomethyl)-5-norbornene ligand. Graphical Abstract  The new platinum(II) compounds PtCl₂(dpmn) (2) and PtMe₂(dpmn) (4) have been synthesized, and their structures established by NMR spectroscopy (¹H and ³¹P) and X-ray crystallography. Compounds 2 and 4 are the first structurally characterized examples of organometallic compounds containing the endo,endo-2,3-bis(diphenylphosphinomethyl)-5-norbornene (dpmn) ligand.

Self-Assembly of Two Isomorphous Thiocyanate Complexes of Co(II) and Ni(II) with 3-Hydroxypicolinamide

Abstract  

The synthesis, thermal and spectral characterization, and crystal structure of isomorphous thiocyanate cobalt(II) and nickel(II) complexes with 3-hydroxypicolinamide (3-OHpia), [M(C₆H₆N₂O₂)₂(NCS)₂]·2H₂O, are reported. The metal(II) ions are chelated by two cis-oriented 3-OHpia and two thiocyanate ligands in distorted octahedral geometry. The distortion within the coordination sphere is mainly imposed by formation of the chelate rings. The compounds crystallize in monoclinic space group P2/c with two symmetrically independent molecules and a = 14.4945(2) ?, b = 8.5906(1) ?, c = 16.3865(3) ?, β = 105.987(2)°, Z = 4 (1) and a = 14.4927(5) ?, b = 8.5912(3) ?, c = 16.2712(6) ?, β = 105.740(4)°, Z = 4 (2). Commonly observed supramolecular amide synthons are not robust enough to accommodate thiocyanate ions and H₂O molecules. But instead, neutral complexes are linked through hydrogen bonds leading to two different hydrogen bonding ribbon motifs involving amide moieties and H₂O molecules [C(8)R ₂²(12) along c axis] and amide moieties and thiocyanate ions [C(8)R ₂²(16) along b axis] for symmetrically related molecules labelled as 1 [Co1 (1) and Ni1 (2)] and 2 [Co2 (1) and Ni2 (2)], respectively.