Synthesis,Characterization and Crystal Structure of Bis(isothiocyanato)-bis(pyridine) Zinc(II) Crystal

Abstract  Bis(isothiocyanato)-bis(pyridine) zinc(II) crystal has been prepared at room temperature and characterized by elemental analysis, IR spectrum and X-ray single crystal determination. The complex crystallizes in monoclinic space group P2₁/m with unit cell parameters: a = 5.5786(3), b = 11.0587(5), c = 12.1616(6) ?, β = 96.776(3)°, V = 745.03(6) ?³, Z = 2, D _x  = 1.514 g cm⁻³. The X-ray structure determination has revealed that the crystal is centered-symmetrical and the crystallographic symmetry face runs the two isothiocyanate ligands and the Zn(II) cation. Index Abstract  The title compound, bis(isothiocyanato)-bis(pyridine) zinc(II), was synthesized by zinc compound, KSCN and C₅H₅N (pyridine) and its crystal structure was determined. Single crystal X-ray structure determination reveals that the crystal is centered-symmetrical, and the crystallographic symmetry face runs the two isothiocyanate ligands and the Zn(II) cation.      

Synthesis and Structural Characterization of Bis(μ2-Iodo)-Bis(Diethyl Ether)-(N-N′-(Bis(2,6-Diisopropylphenyl)Pentane-2,4-Diketiminato)-Lithium-Chromium, a Cr(II) (β-Diketiminato) Complex with a Coordinated LiI Salt

Abstract  Addition of CrI₂ to the lithium salt of N-N′-bis(2,6-diisopropylphenyl)-2,4-diketiminate in diethylether yields a Cr(II) iodide complex with a coordinated, solvated LiI salt. This complex is the intermediate in the synthesis of a bridging iodide complex that is itself a precursor to a side-on bridging dinitrogen complex. This complex crystallizes in the P2₁/n space group with the crystal cell parameters a = 12.3160(19) ?, b = 21.067(3) ?, c = 15.837(3)?, β = 96.767°, V = 4080.6(11) ?³ and Z = 4. Graphical Abstract  Addition CrI2 to the lithium salt of N-N′-bis(2,6- diisopropylphenyl)-2,4-diketiminate in diethylether yields a Cr(II) iodide complex with a coordinated, solvated LiI salt. Herein we report the spectroscopic and structural characterization. An erratum to this article can be found at     

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.      

Synthesis,Crystal Structure and Fluorescent Study of Bis(2-(2-hydroxyphenyl)benzimidazolate)zinc with Ethanol Solvate

Abstract  The zinc(II) complex with 2-(2-hydroxyphenyl)benzimidazole, namely [Zn(2-(2-hydroxyphenyl)benzimidazolate)₂]·C₂H₅OH (1 · C₂H₅OH) has been synthesized and characterized by X-ray crystallography and photoluminescent analysis. The complex crystallizes in monoclinic space group P2₁/c with cell parameters a = 10.156(1) ?, b = 25.771(3) ?, c = 9.674(1) ?, α = 90°, β = 103.641(2)°, γ = 90°, Z = 4, V = 2460.4(4) ?³. The central Zn(II) is four-coordinate and has a tetrahedral geometry. The steady-state and time-resolved photoluminescent spectra for the title compound have also been studied. The emission property can be ascribed to ligand-centered charge-transfer transition (LCCT) with π → π* property. Index Abstract   A new co-crystal of Zn(II) complex of 2-(2-hydroxylphenyl)benzimidazole with ethanol solvate has been prepared, characterized by X-ray crystallography and fluorescent studies.      

Synthesis and Crystal Structure of One Trinuclear di-<Emphasis Type="Italic">n</Emphasis>-butyltin(IV) Complex with Salicylaldoxime

Abstract   One trinuclear di-n-butyltin(IV) complex with salicylaldoxime (o-HON=CHC₆H₄OH=HONZOH), (Bu₂Sn)(Bu₂SnO)(Bu₂SnOH)(ONZOH)(ONZO), has been synthesized and characterized by elemental analyses, IR spectrum, and single crystal X-ray diffraction. This complex is a small cluster displaying two unequivalent salicylaldoximate with one seven-coordinate pentagonal–bipyramidal tin atom linked two five-coordinate trigonal–bipyramidal tin atoms via a network of oxygen atoms by Sn–O–Sn bridges. The hydrogen bonds (o-HON=CHC₆H₄–O…H–O) are observed in the complex. These hydrogen bonds include intramolecular hydrogen bonds and intermolecular hydrogen bonds. (Bu₂Sn)(Bu₂SnO)(Bu₂SnOH)(ONZOH)(ONZO) belongs to monoclinic: space group P2₁/n, with a = 12.2307(15) ?, b = 17.361(2) ?, c = 20.976(3) ?, β = 94.424(2)°, V = 4440.5(10) ?³, Z = 4, D _c  = 1.500 g/cm³, μ(MoKα) = 1.715 mm⁻¹, F(000) = 2024, and final R ₁ = 0.0426, wR ₂ = 0.1064 for observed reflections 7779(I > 2σ(I)). Index abstract  The title compound, di-n-butyltin(IV) complex with salicylaldoxime, was synthesized and its crystal structure determined. Single crystal X-ray diffraction analysis reveals that the molecular structure of the title compound is trinuclear. The complex is a small cluster displaying two unequivalent salicylaldoximate with one seven-coordinate pentagonal–bipyramidal tin atom linked two five-coordinate trigonal–bipyramidal tin atoms via a network of oxygen atoms by Sn–O–Sn bridges.      

Synthesis, Crystal Structure and Fluorescence Property of a Binuclear Zn(II) Complex: [Zn2(μ-N3)2(N3)2(L)2] [L?=?1-(1,10-phenanthrolin-2-yl)-2-pyridone]

Abstract  Hydrated zinc perchlorate reacted with sodium azide and 1-(1,10-phenanthrolin-2-yl)-2-pyridone (L) in methanol solution and resulted in the formation of a new binuclear complex: [Zn₂(μ-N₃)₂(N₃)₂(L)₂]. The complex has been characterized by elemental analysis and IR spectrum, and its crystal structure determined by X-ray crystallography and the complex crystallizes in the monoclinic system with space group P2₁/c and a = 11.409(2), b = 8.0733(15), c = 18.163(3) Ǻ, β = 99.095(3)°. In the complex two azide anions act as bridge ligand and another two azide anion and two 1-(1,10-phenanthrolin-2-yl)-2-pyridone function as terminal ligands, and Zn(II) ion lies in a distorted triangle bipyramid geometry. Index Abstract  The title binuclear Zn(II) complex was synthesized by zinc perchlorate, sodium azide and 1-(1,10-phenanthrolin-2-yl)-2-pyridone and its crystal structure determined. Single crystal X-ray diffraction analysis reveals that azide anion function as both bridge ligand and terminal ligand, and 1-(1,10-phenanthrolin-2-yl)-2-pyridone only acts as a terminal ligand.      

Synthesis, Crystal Structure, Thermal Behavior and IR Characterization of Pentacarbonyl(4-methylpyridine)chromium(0) Complex

Abstract  Pentacarbonyl(4-methylpyridine)chromium(0) complex was isolated from n-hexane solution as yellow plate-like crystals and characterized by using X-ray crystallography. It crystallizes in the orthorhombic system with the space group Cmcm and Z = 4. The unit cell parameters are a = 11.737(1) ?, b = 12.857(2) ?, c = 8.465(1) ?. The single crystal X-ray structure of the complex shows that the coordination sphere around the chromium central atom is slightly distorted octahedron, involving the 4-methylpyridine (4-mp), ligand as a monodentate N-donor ligand and five carbonyl groups. The four equatorial CO groups in the complex, with the Cr–C2 distance of 1.886 Ǻ, are slightly bent away from the 4-methylpyridine ligand with the N–Cr–C2 angle of 91.69°. The pyridine ring plane makes an angle of 135.17° with the Cr–N–CO bond axis. The thermal analysis (differential thermal analysis and thermal gravimetry) and IR spectra of the complex indicated that the compound undergoes complete decomposition to form the Cr₂O₃ as the final decomposition product. Index Abstract  The crystal structure of pentacarbonyl(4-methylpyridine)chromium(0) complex has been determined and its thermal behavior has also been studied.      

Crystal and Molecular Structures of Tris(1-Methylimidazol-2-yl)Phosphine,Tris(4-Methylthiazol-2-yl)Phosphine and its Sulfide

Abstract  Two crystal structures of tris(azolyl)phosphines, PR₃ [R′ = 1-methylimidazol-2-yl (1) or R′′ = 4-methylthiazol-2-yl (2)], and the crystal structure of the sulfurisation product of 2, R′′₃PS (3), were determined. All compounds crystallise in polar space groups, 1 in the orthorhombic space group Pna2₁ with cell parameters a = 13.9779(15) ?, b = 9.2492(10) ? and c = 10.2439(11) ?; 2 in the trigonal space group, R3c, with a = 15.2383(10) ? and c = 10.5882(13) ? and 3 in the orthorhombic space group, Cmc2₁, with a = 13.466(3) ?, b = 9.308(2) ? and c = 12.207(3) ?. Graphical Abstract  This article presents two crystal structures of tris(azolyl)phosphines and one of a tris(thiazolyl)phosphine sulfide, a compound which show potential for wide application in coordination chemistry due to their multidentate nature.      

Synthesis and Characterization of [(1-benzylpyrazole) [<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-bis(2-aminoethyl)-1,2-ethanediamine]copper(II)] Diperchlorate,a Structure with a Sterically Strained,Distorted-Trigonal-Bipyramidal Cation

Abstract  The synthesis, characterization, and molecular structure of the title compound, [(1-benzylpyrazole)[N,N-bis(2-aminoethyl)-1,2-ethanediamine]copper(II)] diperchlorate, [(nbp)(tren)Cu(II)](ClO₄)₂, 2  · 2ClO₄, is reported. The salt crystallized in the monoclinic space group P2₁/n with a = 10.1453(5) ?, b = 17.5250(8) ?, c = 13.6021(6) ?, β = 100.737(19)° and V = 2376.06(19) ?³ with Z = 4. The structure contains copper(II) (nbp)(tren) cations, each with a distorted-trigonal-bipyramidal CuN₅ coordination geometry, separated by perchlorate anions. The cations exhibit steric strain associated primarily with close contacts between the methylene protons of the nbp ligand and one of the amine groups of the tren ligand. The strain has a noticeable effect on the coordination geometry and certain physical properties of the complex. Graphical Abstract  In the title structure, steric strain in the (nbp)(tren)Cu(II) cations, associated with close contacts between protons of the nbp ligand and two of the amine groups of the tren ligand (dashed lines in the figure below) affects certain physical properties of the cation and is consistent with an anomalously long Cu(II)–N(pyrazole) distance (Cu–N41) and an unusually large axial–equatorial angle, N41–Cu–N12.      

4-Chloro-2,6-bis(hydroxymethyl)pyridinium Chloride and 4-Dimethylamino-2,6-bis(hydroxymethyl)pyridinium Chloride Hemihydrate

Abstract  Two substituted pyridinium chloride salts, namely 4-chloro-2,6-bis(hydroxymethyl)pyridinium chloride (triclinic, P-1, a = 6.0651(8) ?, b = 8.4393(8) ?, c = 8.6554(9) ?, α = 78.845(1)°, β = 83.156(1)°, γ = 89.047(1)°; V = 431.55(8) ?³; Z = 2) and 4-dimethylamino-2,6-bis(hydroxymethyl)pyridinium chloride hemihydrate (orthorhombic, Aba2, a = 17.2179(14) ?, b = 17.6332(15) ?, c = 7.2068(6) ?; V = 2188.0(3) ?³; Z = 4), have been structurally characterized. Hydrogen bonding and van der Waals contacts are evident in both structures. Furthermore, the 4-dimethylamino derivative features a trigonal planar dimethylamino group with some π interaction between the nitrogen atom and the pyridine ring. Graphical Abstract  Two compounds, namely 4-chloro-2,6-bis(hydroxymethyl)pyridinium chloride and 4-dimethylamino-2,6-bis(hydroxymethyl)pyridinium chloride hemihydrate, have been spectroscopically and structurally characterized.      

Synthesis and Crystal Structure a Two-Dimensional Coordination Polymer: [Cd( μ -N3)( μ -HL)(H2O)]n [HL?=?Monodeprotonated 2,2′-bypyridine-3,3′-diol]

Abstract  Hydrated cadmium perchlorate reacted with sodium azide and 2,2′-bypyridine-3,3′-diol (H₂L) in ethanol solution and resulted in the formation of a two-dimensional coordination polymer: [Cd(μ-N₃)(μ-HL)(H₂O)]_n. The complex has been characterized by elemental analysis and IR spectrum, and its crystal structure determined by X-ray crystallography and the complex crystallizes in the monoclinic system with space group P2₁/c and a = 7.2849(14), b = 9.9568(19), c = 17.058(3) Ǻ, β = 102.254(2)°. In the complex both azide anion and monodepronated 2,2′-bypyridine-3,3′-diol anion (HL) act as bridge ligands and led to the formation of a two-dimensional sheet structure on (100) plane, and the O–H⋯N hydrogen bond made the sheets pile up along [100] direction, which forms a supramolecular three-dimensional structure. Graphical Abstract  The title two-dimensional Cd(II) coordination polymer was synthesized by cadmium perchlorate, sodium azide and 2,2′-bypyridine-3,3′-diol and its crystal structure determined. Single crystal X-ray diffraction analysis reveals that the two-dimensional coordination polymer was fabricated with azide anion and monodeprotonated 2,2′-bypyridine-3,3′-diol as mixed bridge ligands.      

Synthesis,Characterization and Crystal Structure Determination of a Hepta-coordinated Cadmium(II) Complex with Thiocyanato-bridges

Abstract  A new cadmium(II) complex [(C₂₈H₂₄N₆)Cd(SCN)₂]₂(CH₃OH)₂ (1) has been synthesized and characterized by IR, UV spectra, TG-DTA technique and single crystal X-ray diffraction analysis. The crystallographic data for compound 1: triclinic P1ˉ, a = 9.630(2) Å, b = 11.123(3) Å, c = 15.396(4) Å, α = 106.93(1)°, β = 91.60(1)°, γ = 99.99(1)°, V = 1,548.5(6) Å³, Z = 1, Dc = 1.512 mg/m³, F(000) = 716, R ₁ = 0.0332, wR ₂ = 0.0907. The molecule contains a symmetrical dinuclear unit in which two Cd(II) ions are double bridged by two di-μ-1,3-SCN⁻ anoins with a cadmium–cadmium separation of 6.48 Å. Each Cd(II) ion is seven-coordinated with six nitrogen atoms and a sulfur atom to form a monocapped trigonal prism coordination geometry. In addition, the molecule is further connected by multiform intermolecular C–H···π, π···π interactions and hydrogen bonds to form a three-dimensional supramolecular structure. Graphical Abstract  A hepta-coordinated Cd(II) complex which exhibits a distorted a monocapped trigonal prism coordination geometry has been achieved by using bisbidentate Schiff-base ligand and thiocyanate anion.      

Synthesis and Crystal Structure of a Mixed-Ligand Cobalt(II) Complex with 2-Aminobenzimidazole

Abstract  The cobalt(II) complex, [Co(abz)₂(SCN)₂] 1, has been synthesized by the reaction of cobalt(II) nitrate with ammonium thiocyanate and abz ligands (abz = 2-aminobenzimidazole), and was fully structurally characterized by elemental analysis, IR spectra, X-ray diffraction and thermogravimetric experiments. It crystallizes in the triclinic P-1 space group with a = 8.6316(10), b = 9.3426(10), c = 13.254(2) ?, α = 95.793(2), β = 95.870(2), γ = 115.7380(10), V = 945.1(2) ?³, and Z = 2. The central cobalt(II) atom is four-coordinated to nitrogen donors from two neutral abz ligands and two isothiocyanate anions respectively, adopting a slightly distorted tetrahedral geometry. In addition, the intermolecular N–H···N and N–H···S hydrogen bonds interactions link the discrete mononuclear units into infinite three-dimensional networks. Index Abstract  The essence sentence of the paper: In the mixed-ligand mononuclear complex, [Co(abz)₂(SCN)₂], the four coordinated cobalt(II) atom exhibits a slightly distort tetrahedron, which is further assembled into 3D infinite network by intermolecular hydrogen interactions.      

The First Coordination Compound with 5-methylisoxazole-3-carboxylate: Synthesis and Structural Characterization of [Cu(L<Subscript>2</Subscript>)(H<Subscript>2</Subscript>O)] · H<Subscript>2</Subscript>O

Abstract  The title compound, aquabis(5-methylisoazole-3-carboxylato-O,N)copper(II) monohydrate, [Cu(L₂)(H₂O)] · H₂O is synthesized and characterized by X-ray diffraction, elementary analysis, and IR. The ligand coordinates to the copper center in a bidentate O,N fashion through the carboxylic acid moiety and the heteroaromatic nitrogen atom. The complex crystallizes in the triclinic space group with unit cell parameters a = 8.4080(12)?, b = 8.810(3), c = 10.318(2)?, α = 110.08(3)°, β = 104.81(2)°, γ = 103.149(16)°, V = 650.9(3)?³, Z = 2. In addition, the synthesis of the free acid 5-methylisoazole-3-carboxylic acid and pyridine containing complex bis(5-methylisoazole-3-carboxylato)bispyridinecopper(II) monohydrate is described. Index Abstract  Synthesis and crystal structure of aquabis(5-methylisoazole-3-carboxylato-O,N)copper(II)monohydrate. The first coordination compound of 5-methylisoxazole-3-carboxylic acid.      

Crystal Structure and Magnetic Properties of a Novel Octa-coordinated Manganese(II) Complex

Abstract  The self-assembly and structural characterization of the new manganese(II) [MnL ₂](ClO₄)₂(CH₃OH)_0.5 (1) complex has been achieved. The crystallographic data for the complex 1: Orthorhombic Pbca , a = 16.287(2) ?, b = 21.293(2)?, c = 32.718(3) ?, V = 11,347(2) ?³, Z = 8. The two polydentate ligands strand intertwined each other and around the manganese(II) ions forming a mononuclear complex. The Mn(II) ion is eight-coordinated with the eight donor nitrogen atoms of two ligands to form a distorted square antiprismatic coordination geometry. The magnetic properties investigation indicates that there is a weak antiferromagnetic exchange coupling between the Mn(II) ions of the complex. Index Abstract  An octa-coordinated Mn(II) complex which exhibits a distorted square antiprismatic coordination geometry has been achieved by using a bisbidentate Schiff-base ligand.      

Synthesis and Structural Characterization of Bis[(cyclohexylamino)pent-2-en-4-onato]-Chromium(II)

Abstract  Addition of one equivalent of CrI₂ to two equivalents of lithium cyclohexylamino-pent-2-en-4-onate results in bis[(cyclohexylamino)pent-2-en-4-onato]-chromium(II). Crystallization in diethylether reaction solvent forms the hemi-etherate A with the asymmetric unit showing two target compounds and one molecule of cocrystallized diethylether in the P-1 space group with crystal cell parameters a = 12.931(4) Å, b = 13.207(4) Å, c = 16.104(5) Å, α = 66.559(5)°, β = 77.670(5)°, γ = 81.562(5)°, V = 2,459.1(14) Å³ and Z = 4. Drying A in vacuo and recrystallization in pentane yields a nonsolvated crystalline phase B with an asymmetric unit displaying only one molecule of the target compound in the P2₁/c space group with crystal cell parameters a = 14.290(7) Å, b = 14.082(7) Å, c = 11.246(6) Å, β = 94.807(8)°, V = 2,255.1(19) Å³ and Z = 4. Graphical Abstract  A Cr(II) complex supported by two β-enaminoketiminato ligands, bis[(cyclohexylamino)pent-2-en-4-onato]-chromium(II), has been synthesized and has been structurally characterized in two different crystal phases.      

Crystal of Tetrakis(1-ethyl-1H-imidazole)diisothiocyanatocopper(II) bis(1-ethyl-1H-imidazole)diisothiocyanatocopper(II)

Abstract  A new complex [Cu(NCS)₄ (N-Eim)₄] [Cu(NCS)₂ (N-Eim)₂] (where N-Eim = N-ethylimidazole) has been synthesized and structurally characterized by single-crystal X-ray diffraction. The compound crystallizes in the Triclinic space group P−1 with the parameters: a = 8.7707(18) ?, b = 10.712(2) ?, c = 13.511(3) ?, α = 104.73(3)°, β = 104.84(3)°, γ = 102.52(3)°, V = 1131.54(3) ?³, with Z = 1 formula units. In the structure, the copper atoms all assume an elongated octahedral geometry with two distinct coordination environments; one is coordinated by four N-ethyl-imidazole ligands and two axial SCN groups, and another by two SCN groups and two N-ethyl-imidazole ligands. The two units form one infinite 1D zigzag chain along the [1 0 1] plane by two thiocyanate ligands from the [Cu(NCS)₄ (N-Eim)₄] units. Index Abstract  The title compound, tetrakis(1-ethyl-1H-imidazole)diisothio cyanatocopper(II) bis(1-ethyl-1H-imidazole)diisothiocyanatocopper(II) has been synthesized and structurally characterized by single-crystal X-ray diffraction. In the structure, the copper atoms all assume an elongated octahedral geometry with two distinct coordination environments. The two units form one infinite 1D zigzag chain along the [1 0 1] plane by two thiocyanate ligands from the [Cu(NCS)₄ (N-Eim) 4] units.      

Synthesis and Structural Characterization of <Emphasis Type="Italic">N</Emphasis>-(2-Pyridylmethyl)-3-Methoxysalicylaldiminato Copper(II) Chloride

Abstract  The copper(II) complex [Cu(C₅H₄NCH₂−N=CH–C₆H₃OCH₃–O)Cl], (1) containing a new tridentate Schiff base ligand (LH), which is the 1:1 condensation product of 2-(aminomethyl)pyridine and o-vaniline, has been synthesised and characterized by IR and UV–Vis spectra. Structural investigation shows that 1 crystallizes to a monoclinic system, having space group P2(1)/c, a = 6.9634(7), b = 18.1209(19), c = 10.3448(11) ?, α = 90°, β = 103.97(2)°, γ = 90° and Z = 4. The coordination geometry around the copper atom is slightly distorted square planar, formed by the N₂O donor set of the Schiff base and one Cl atom. The Cu–N(1), Cu–N(2), Cu–O(1) and Cu–Cl bond distances are 2.0114(14), 1.9414(14), 1.9147(12) and 2.2520(5) ?, respectively. Index Abstract  The copper(II) complex [Cu(C₅H₄NCH₂−N=CH–C₆H₃OCH₃–O)Cl], (1) containing a tridentate Schiff base ligand (LH), synthesised and characterized by IR and UV–Vis spectra. The central copper ion possesses a distorted square-planar geometry.      

An X-Ray Crystallographic Study of the Novel Aminal bis-(<Emphasis Type="Italic">p</Emphasis>-Ethoxycarbonylphenylamino-)methane

Abstract  The crystal structure of bis-(p-Ethoxycarbonylphenylamino-)methane (1) has been determined by single crystal X-ray diffraction analysis. The bis-aminal (1) molecule is V-shaped and situated on a twofold axis passing through C1 with the phenyl rings forming a dihedral angle of 70.2(1)°. The carboxylate and phenyl groups are coplanar. The crystal structure of 1 is compared with the structure of the closely related aminals, 2–5. Crystal data: 1 C₁₉H₂₂N₂O₄, tetragonal, space group I4 ₁ cd (N.110), a = 20.4760(7) Ǻ, b = 20.4760(7) Ǻ, c = 8.2984(3) ?, and V = 3477.7(2) ?³, for Ζ = 8. Index Abstract  The crystal structure of bis-(p-ethoxycarbonylphenylamino-)methane (1) has been determined by single crystal X-ray diffraction analysis.