Toluene Solvent Molecules Research Articles

Solvent Geometry Regulated J- and H-Type Aggregates of Photoswitchable Organogelator: Phase-Selective Thixotropic Gelation and Oil Spill Recovery.

We demonstrate supramolecular polymerization and formation of 1D nanofiber of azobenzene based organogelator (AZO-4) in cyclic hydrocarbon solvents (toluene and methylcyclohexane). The AZO-4 exhibits J- and H-type aggregates in toluene: MCH (9 : 1) and MCH: toluene (9 : 1) respectively. The type of aggregate was governed by the geometry of the solvents used in the self-assembly process. The J-type aggregates with high thermal stability in toluene is due to the enhanced interaction of AZO-4 π- surface with the toluene π-surface, whereas H-aggregate with moderate thermal stability in MCH was due to the interruption of the cyclic hydrocarbon in van der Waals interactions of peripheral chains of AZO-4 molecule. The light induced reversible photoisomerization is observed for both J- and H-aggregates. The macroscopic property revealed spontaneous and strong gelation in toluene preferably due to the strong interactions of the AZO-4 nanofibers with the toluene solvent molecules compared to the MCH. The rheological measurements revealed thixotropic nature of the gels by step-strain experiments at room temperature. The thermodynamic parameter (ΔHm) of gel-to-sol transition was determined for all the gels to get more insight into the gelation property. Furthermore, the phase selective gelation property was extended to the oil spill recovery application using diesel/water and petrol/water mixture.

Crystal structures of the Lewis acid-base adducts {[(C6H11)2N]3Ti-LB}+[MeB(C6F5)3]-·1.5C7H8; LB = (C6H5)3PO (1), p-F-C6H4CN (2).

The reaction of [(C6H11)2N]3Ti-CH3 with the Lewis acid B(C6F5)3, followed by addition of the Lewis bases (C6H5)3PO and p-F-C6H4CN led to the complex salts tris-(di-cyclo-hexyl-amido)(tri-phenyl-phosphine oxide)titanium methyl-tris(penta-fluoro-phen-yl)borate toluene sesquisolvate, [Ti(C12H22N)3(C18H15OP)](C19H3F15B)·1.5C7H8, (1), and tris-(di-cyclo-hexyl-amido)(4-fluoro-benzo-nitrile)-titanium methyl-tris-(penta-fluoro-phen-yl)borate toluene sesquisolvate, [Ti(C12H22N)3(C7H4FN)](C19H3F15B)·1.5C7H8, (2), both crystallizing with 1.5 equivalents of toluene solvent mol-ecules. The Lewis acid-base adducts (1) and (2) can be described by dative donor bonds. The packing of the complex cations, anions and solvent mol-ecules in the crystal structure is consolidated by an intricate three-dimensional network of non-classical C-H⋯F inter-actions. Disorder of some of the cyclo-hexyl groups and the toluene solvent mol-ecules is observed.

Crystal structure of bis(5-bromo-1,10-phenanthroline-κ2 N,N')bis-[di-hydro-bis-(pyrazol-1-yl)borato-κ2 N 2,N 2']iron(II) toluene disolvate.

The structure determination of the title compound was undertaken as part of a project on the modification and synthesis of new spin-crossover (SCO) compounds based on octa-hedral FeII bis-(pyrazol-yl)borate complexes. In the course of these investigations, the compound [Fe(C6H8BN4)2(C12H7BrN2)] was synthesized, for which magnetic measurements revealed an incomplete spin-crossover behaviour. Crystallization of this compound from toluene led to the formation of crystals of the toluene disolvate, [Fe(C6H8N4B)2(C12H7N2Br)]·2C7H8. Its asymmetric unit comprises two discrete metal complex mol-ecules and two toluene solvent mol-ecules. One of the latter is severely disordered and its contribution to the diffracted intensities was removed using the SQUEEZE routine [Spek (2015 ▸). Acta Cryst. C71, 9-18]. In each complex mol-ecule, the FeII cation is coordinated by the two N atoms of a 5-bromo-1,10-phenanthroline ligand and by two pairs of N atoms of chelating di-hydro-bis(pyrazol-1-yl)borate ligands in the form of a slightly distorted octa-hedron. The discrete complexes are arranged in columns along the a-axis direction with the toluene solvate mol-ecules located between the columns. The 5-bromo-1,10-phenanthroline ligands of neighbouring columns are approximately parallel and are slightly shifted relative to each other, indicating π-π inter-actions.

Molecular-Scale Ligand Effects in Small Gold–Thiolate Nanoclusters

Because of the small size and large surface area of thiolate-protected Au nanoclusters (NCs), the protecting ligands are expected to play a substantial role in modulating the structure and properties, particularly in the solution phase. However, little is known on how thiolate ligands explicitly modulate the structural properties of the NCs at atomic level, eventhough this information is critical for predicting the performance of Au NCs in application settings including as a catalyst interacting with small molecules and as a sensor interacting with biomolecular systems. Here, we report a combined experimental and theoretical study, using synchrotron X-ray spectroscopy and quantum mechanics/molecular mechanics simulations, that investigates how the protecting ligands impact the structure and properties of small Au18(SR)14 NCs. Two representative ligand types, smaller aliphatic cyclohexanethiolate and larger hydrophilic glutathione, are selected, and their structures are followed experimentallyin both solid and solution phases. It was found that cyclohexanethiolate ligands are significantly perturbed by toluene solvent molecules, resulting in structural changes that cause disorder on the surface of Au18(SR)14 NCs. In particular, large surface cavities in the ligand shell are created by interactions between toluene and cyclohexanethiolate. The appearance of these small molecule-accessible sites on the NC surface demonstrates the ability of Au NCs to act as a catalyst for organic phase reactions. In contrast, glutathione ligands encapsulate the Au NC core via intermolecular interactions, minimizing structural changes caused by interactions with water molecules. The much better protection from glutathione ligands imparts a rigidified surface and ligand structure, making the NCs desirable for biomedical applications due to the high stability and also offering a structural-based explanation for the enhanced photoluminescence often reported for glutathione-protected Au NCs.

Group 4 metal complexes containing the salalen ligands: Synthesis, structural characterization and studies on the ROP of cyclic esters

The synthesis of homoleptic salalen ligand supported group 4 complexes and their applications in the ring-opening polymerization (ROP) of ε-caprolactone (ɛ-CL) and lactide (LA) are described. All these complexes of type M(L)2 (LH = (E)-N-(2-(3,5-dibromo-2-hydroxybenzylideneamino)phenyl)-4-methylbenzenesulfonamide: M = Ti (1), M = Zr (4), M = Hf (7); LH = (E)-N-(2-(2-hydroxybenzylideneamino)phenyl)-4-methylbenzenesulfonamide: M = Ti (2), M = Zr (5), M = Hf (8); LH = (E)-N-(2-(3,5-di-t-butyl-2-hydroxybenzylideneamino)phenyl)-4-methylbenzenesulfonamide: M = Ti (3), M = Zr (6), M = Hf (9)) are characterized by various spectroscopic techniques. The single crystal X-ray diffraction analysis confirmed that the metal centres in complexes 6 and 8 adopt distorted dodecahedral geometry. The self-assembly of the complexes in solid state through the molecular interactions demonstrated that the supramolecular network forms molecular channels which act as a host lattice for the assembly of toluene solvent molecules. Complexes (1–9) are effective catalysts for the ROP of ɛ-CL and LA and produced high molecular weight (Mn) polycaprolactone (PCL) and poly (lactic acid) (PLA) respectively with narrow molecular weight distributions (MWDs) in the range of 1.17–1.28. PLA produced from the polymerization of rac-LA is atactic. However, better control over the polymerization process was achieved in the presence of toluene as solvent at 80 °C. All these polymerizations follow first-order kinetics with respect to monomer concentration. MALDI-TOF and NMR spectral analysis suggested that the polymerization proceeds through the coordination-insertion mechanism.

Crystal structures of a novel NNN pincer ligand and its dinuclear titanium(IV) alkoxide pincer complex.

This report describes a synthetic protocols and the crystal structures involving a novel pincer-type H3[NNN] ligand, namely di-μ-bromido-μ-{2-(2,2-di-methylpropanimido-yl)-N-[2-(2,2-di-methyl-propanimido-yl)-4-methyl-phen-yl]-4-methylaniline}-bis-[(diethyl ether)lithium], [Li2Br2(C24H33N3)(C4H10O)2] (1) and a dinuclear metal complex, namely di-μ-bromido-2:3κ4Br:Br-bis-{2-(2,2-di-methylpropanimido-yl)-N-[2-(2,2-di-methyl-propanimido-yl)-4-methyl-phen-yl]-4-methylaniline}-1κ3N,N',N'';4κ3N,N',N''-tetra-μ-iso-propano-lato-1:2κ4O:O;3:4κ4O:O-diiso-propano-lato-1κO,4κO-2,3-dilithium-1,4-dititanium, [Li2Ti2Br2(C24H32N3)2(C3H7O)6] or {[NHNNH]Ti(O i Pr)3(LiBr)2}2 (2). Complex 1, which sits on a twofold rotation axis, is a rare example of a pincer-type ligand which bears ketimine side arms. A unique feature of complex 1 is that the ketimine N atoms have an LiBr(Et2O) fragment bonded to them, with the Li atom adopting a distorted tetra-hedral geometry. This particular fragment creates an LiBr bridge between the two ketimine sidearms, which leads to a cage-type appearance of the ligand. Complex 2 consists of the previously described ligand and a TiIV metal atom in an octa-hedral environment, and is located on an inversion center. Complex 2 crystallizes as a dinuclear species with the metal atoms being bridged by an LiBr entity [the Br atoms are disordered and refined in two positions with their site occupation factors refining to 0.674 (12)/0.372 (12)], and the Li cation being bonded to the isopropoxide O atoms (Li having a tetra-hedral coordination as in 1). The organic ligand of compound 2 exhibits disorder in its periphery groups; isopropyl and tert-butyl groups (occupation factors fixed at 0.6/0.4). The novel [NNN]H3 pincer-type ligand was characterized by multinuclear and multidimensional NMR, HRMS and X-ray crystallography. The dinuclear metal complex 2 was characterized by X-ray crystallography. Although each structure exhibits donor N-H groups, no hydrogen bonding is found in either one, perhaps due to the bulky groups around them. One of the ethyl groups of the ether ligand of 1 is disordered and refined in two parts with site-occupation factors of 0.812 (8) and 0.188 (8). One and a half toluene solvent mol-ecules are also present in the asymmetric unit of 2. The toluene mol-ecules were significantly disordered and could not be modeled properly, thus SQUEEZE [Spek (2015 ▸). Acta Cryst. C71, 9-18] was used to remove their contributions to the overall intensity data.

{2-[Bis(2,4-di-tert-butylphenoxy)phosphanyloxy-κP]-3,5-di-tert-butylphenyl-κC1}{3,3′-di-tert-butyl-5,5′-dimethoxy-2,2′-bis[(1,1,2,2-tetraphenylethane-1,2-dioxy)phosphanyloxy-κP]biphenyl}rhodium(I) toluene-d82.7-solvate

The molecule of the title compound, [Rh(C42H62O3P)(C74H68O4P2]·2.7C7D8, consists of two phospharhodacyclic substructures sharing the Rh atom, which are formed by coordination/ortho-metallation of a triaryl phosphite, and by the coordination of a rigid bisphosphite, respectively. The metal displays a tetrahedrally distorted square-planar coordination geometry. Atert-butyl group shows rotational disorder over two positions with refined site occupancy of 0.561 (3):0.439 (3). Two partial-occupancy toluene solvent molecules are disordered over two orientations with site occupancies of 0.5:0.3 and 0.5:0.4, respectively. Intramolecular C—H...O hydrogen bonds are observed. In the crystal, complex molecules and toluene solvent molecules pack as alternating layers parallel to theacplane.

Crystal structures of two ansa-titanocene tri-fluoro-methane-sulfonate complexes bearing the Me2Si(C5Me4)2 ligand.

The crystal structures of two ansa-titanocene tri-fluoro-methane-sulfonate complexes bearing the Me2Si(C5Me4)2 ligand are reported, namely [di-methylbis-(η5-tetra-methyl-cyclo-penta-dien-yl)silane](tri-fluoro-methane-sulfonato-κ2O,O')titanium(III) toluene monosolvate, [Ti(CF3O3S)(C20H30Si)]·C7H8, 1, and chlorido-[di-methyl-bis-(η5-tetra-methyl-cyclo-penta-dien-yl)silane](tri-fluoro-methane-sulfonato-κO)titanium(IV), [Ti(CF3O3S)(C20H30Si)Cl], 2. Both complexes display a bent metallocene unit, the metal atom being coordinated in a distorted tetra-hedral geometry, with the tri-fluoro-methane-sulfonate anion acting as a bidentate or monodentate ligand in 1 and 2, respectively. In 1, weak π-π stacking inter-actions involving the toluene solvent mol-ecules [centroid-to-centroid distance = 3.9491 (11) Å] are observed.

Crystal structure of a dimeric β-diketiminate magnesium complex.

The solid-state structure of a dimeric β-diketiminate magnesium(II) complex is discussed. The compound, di-μ-iodido-bis-[(-{4-amino-1,5-bis-[2,6-bis-(propan-2-yl)phen-yl]pent-3-en-2-yl-idene}aza-nido-κ2N,N')magnesium(II)] toluene sesquisolvate, [Mg2(C29H41N2)2I2]·1.5C7H8, crystallizes as two independent mol-ecules, each with 2/m crystallographic site symmetry, located at Wyckoff sites 2c and 2d. These have symmetry-equivalent magnesium atoms bridged by μ-iodide ligands with very similar Mg-I distances. The two Mg atoms are located slightly below (∼0.5 Å) the least-squares plane defined by N-C-C-N atoms in the ligand scaffold, and are approximately tetra-hedrally coordinated. One and one-half toluene solvent mol-ecules are disordered with respect to mirror-site symmetry at Wyckoff sites 4i and 2a, respectively. In the former case, two toluene mol-ecules inter-act in an off-center parallel stacking arrangement; the shortest C to C' (π-π) distance of 3.72 (1) Å was measured for this inter-action.

Crystal structures of two ytterbium(III) complexes comprising alkynylamidinate ligands.

Two ytterbium(III) complexes comprising alkynylamidinate ligands, namely bis-(η5-cyclo-penta-dien-yl)(3-cyclo-propyl-N,N'-diiso-propyl-propynamidinato-κ2N,N')ytterbium(III), [Yb(C5H5)2(C12H19N2)] or Cp2Yb[( i Pr2N)2C-C≡C-c-C3H5] (1) and tris-(3-phenyl-N,N'-di-cyclo-hexyl-propynamidinato-κ2N,N')ytterbium(III), [Yb(C21H27N2)3] or Yb[(CyN)2C-C≡C-Ph]3 (Cy = cyclo-hex-yl) (2) have been synthesized and structurally characterized. Both complexes are monomers; for complex 2, the contribution to the scattering from highly disordered toluene solvent molecules in these voids was removed with the SQUEEZE routine [Spek (2015). Acta Cryst. C71, 9-18] in PLATON. The stated crystal data for Mr, μ etc. do not take these into account.

Crystal structures of three substituted 3-aryl-2-phenyl-2,3-di-hydro-4H-1,3-benzo-thia-zin-4-ones.

Three ring-substituted 3-aryl analogs of 2-phenyl-2,3-di-hydro-4H-1,3-benzo-thia-zin-4-one, namely 3-(4-meth-oxy-phen-yl)-2-phenyl-4H-1,3-benzo-thia-zin-4-one, C21H17NO2S, (I), 2-phenyl-3-[4-(tri-fluoro-meth-yl)phen-yl]-2,3-di-hydro-4H-1,3-benzo-thia-zin-4-one toluene hemisolvate, C21H14F3NOS·0.5C7H8, (II), and 3-(3-bromo-phen-yl)-2-phenyl-2,3-di-hydro-4H-1,3-benzo-thia-zin-4-one toluene hemisolvate, C20H14BrNOS·0.5C7H8, (III), were synthesized and their crystal structures determined. The hemisolvates differ in that in (II), the asymmetric unit comprises two molecules of the benzo-thia-zinone compound and a toluene solvent mol-ecule, whereas in (III), the unit comprises one benzo-thia-zinone mol-ecule and a half-occupancy toluene solvent mol-ecule. All crystals are of racemic mixtures of the chiral 2-C atom of the thia-zine moiety, which in all structures has a screw-boat puckering, with the puckering amplitude values within the range 0.575-0.603 Å. In all three structures, the benzene plane of the benzo-thia-zine system makes a dihedral angle in the range 78.60 (5) to 98.40 (5)° with the unsubstituted benzene plane and in the range 70.50 (1) to 121.00 (5)° with the substituted benzene plane. The CF3 substituent group in one of the mol-ecules of (II) shows positional disorder, with an occupancy ratio of 0.57 (3):0.43 (3). In the crystals of (I) and (II), weak inter-molecular C-H⋯O inter-actions are present, giving in (I), mol-ecules arranged in a plane parallel to (010), and in (II), chains along a. In addition, all three structures show weak C-H⋯π inter-actions involving various aromatic rings.

Solid-state assembly of a resorcin[6]arene in twin molecular capsules

The solid state structures of a resorcin[6]arene macrocycle crystallized in two different forms are here reported. In both instances, the molecule adopts a pinched cone conformation very similar to that of p-tert-butylcalix[6]arene. In one case, the resorcin[6]arene macrocycle self-assembles in a molecular capsule able to host toluene and ethyl acetate solvent molecules.

Crystal structure of a mixed-valence μ-oxide Sn12 cluster.

The mixed-valence μ-oxide Sn12 cluster, deca­carbonyl­tetra-μ4-oxido-hexa-μ3-oxido-tetra­kis­[μ-2,2′-(pyridine-2,6-di­yl)bis(1,1-di­phenyl­ethano­lato)]deca­tin(II)ditin(IV)dimolyb­denum(O)(2 Mo—Sn) toluene hepta­solvate, [Mo2Sn12(C33H27NO2)4O10(CO)10]·7C7H8, has a crystallographically imposed inversion centre. The asymmetric unit also contains three and a half toluene solvent mol­ecules, one of which is disordered about a centre of symmetry. The complex mol­ecule comprises six distinct Sn atom species with four different coordination numbers, namely 3, 4, 5, and 6. The SnII atoms forming the central Sn10O10 core adopt distorted trigonal–pyramidal, square-pyramidal and octa­hedral coordination geometries provided by the μ-oxide atoms and by the O- and N-donor atoms of two pyridinedi­ethano­late ligands. The terminal SnIV atoms have distorted trigonal–bipyramidal coordination geometries, with a μ4-oxide atom and the N atom of a pyridinedi­ethano­late ligand occupying the axial positions, and the Mo atom of a Mo(CO)5 group and the alk­oxy O atoms of a ligand forming the equatorial plane. In the crystal, weak intra- and inter­molecular C—H⋯O hydrogen bonds are observed.

4-tert-Butyl-pyridinium chloride-4,4'-(propane-2,2-di-yl)bis-(2,6-di-methyl-phenol)-toluene (2/2/1).

In the title solvated salt, C9H14N+·Cl−·C19H24O2·0.5C7H7, two mol­ecules of 4,4′-(propane-2,2-di­yl)bis­(2,6-di­methyl­phenol) are linked via O—H⋯Cl hydrogen bonds to two chloride ions, each of which is also engaged in N—H⋯Cl hydrogen bonding to a 4-tert-butyl­pyridinium cation, giving a cyclic hydrogen-bonded entity centred at 1/2, 1/2, 1/2. The toluene solvent mol­ecule resides in the lattice and resides on an inversion centre; the disorder of the methyl group requires it to have a site-occupancy factor of 0.5. No crystal packing channels are observed.

The Effect of Explicit Solvent on Photodegradation of Decabromodiphenyl Ether in Toluene: Insights from Theoretical Study

Polybrominated diphenyl ethers (PBDEs) have received special environmental concern because of their potential toxicity to humans and wildlife worldwide. However, their photochemical degradation mechanisms remain largely unknown. Herein, a PCM/TD-DFT scheme (time-dependent density functional theory combined with the polarizable continuum model) augmented with explicit solute-solvent interactions is used to explore the promotive effects of the toluene solvent on the photochemical degradation debromination of deca-BDE (BDE209). The face-to-face π-π interactions between penta-bromine-substituted phenyl and toluene are investigated. The calculations indicate that the face-to-face π-π interaction plays an important role in the low-lying π→σ* transitions of BDE209-toluene π-stacking complex at around 300 nm in the sunlight region, which leads to notable changes for the πσ* excited states and which promotes the breaking of the C-Br bonds. The photodegradation reaction via an intermolecular charge-transfer excited state formed by the electronic transition from a π orbital of toluene to a σ* orbital of BDE209 is found to be a dominant mechanism. Our calculation results reveal the mechanism of how the participation of an explicit toluene solvent molecule catalyzes the photodegradation of BDE209 and explain the experimental results successfully. The present study may provide helpful information for the removal of PBDE contamination.

The correct assignment of stereochemistry in di-μ-dichlorido-bis{bis[2-(5-benzylsulfonyl)-3-fluoro-2-(pyridin-2-yl)phenyl-κ2N,C1]iridium(III)} toluene monosolvate

The title complex, [Ir2(C18H13FNO2S)4Cl2]·C7H8, was crystallized from dichloromethane solution under a toluene atmosphere. It is a dimeric complex in which each of the two Ir(III) centres is octahedrally coordinated by two bridging chloride ligands and by two chelating cyclometalated 2-(4-benzylsulfonyl-2-fluorophenyl)pyridine ligands. The crystal structure analysis unequivocally establishes the trans disposition of the two cyclometalated ligands bound to each Ir(III) centre, contrary to our previous hypothesis of a cis disposition. The latter was based on the (1)HNMR spectra of a series of dimeric benzylsulfonyl-functionalized dichloride-bridged iridium complexes, including the compound described in the present work [Ragni et al. (2009). Chem. Eur. J. 15, 136-148]. The toluene solvent molecules, embedded in cavities in the crystal structure, are highly disordered and could not be modelled successfully; their contribution was removed from the refinement using the SQUEEZE routine in the program PLATON [Spek (2009). Acta Cryst. D65, 148-155].

A dinuclear zinc complex containing a diamond-core geometry: [Zn2(μ2-GueO)2(GueO)2(py)2]·0.5(toluene) (GueOH is guethol)

The title zinc alkoxide, bis(μ-2-ethoxyphenolato)-κ(3)O(1),O(2):O(1);κ(3)O(1):O(1),O(2)-bis[(2-ethoxyphenolato-κ(2)O(1),O(2))(pyridine-κN)zinc(II)] toluene hemisolvate, [Zn2(C8H9O2)4(C5H5N)2]·0.5C7H8, crystallizes with two independent complex molecules located on inversion centres and one independent toluene solvent molecule disordered about an inversion centre. The Zn(II) atoms are six-coordinated in distorted octahedral geometries with O5N donor sets. The Zn(II) ions and bridging alkoxide groups are arranged in a diamond Zn2O2 core structure. The guetholate (2-ethoxyphenolate) ligands adopt two different coordination modes, viz. peripheral chelating and μ2-bridging. Preliminary investigations of the catalytic activity of the compound in the ring-opening polymerization of L-lactide demonstrate rapid and efficient generation of polylactide.

Di-μ-sulfido-bis{[rac-1,2-bis(η5-4,5,6,7-tetrahydroinden-1-yl)ethane]zirconium(IV)} toluene monosolvate

The title dimeric zirconium complex, [Zr2(C20H24)2S2]·C7H8, was obtained from the reaction of (ebthi)Zr(η2-Me3Si–C2–SiMe3) [ebthi is rac-1,2-bis­(η5-4,5,6,7-tetra­hydro­inden-1-yl)ethane] and S=C=N-ada (ada = adamantan-1-yl) along with the formation of the isonitrile C N-ada. Each ZrIV atom is coordinated by the sterically hindered ebthi ligand and two μ-sulfide ligands in a strongly distorted tetra­hedral geometry. The [ZrS]2 unit is almost planar (mean deviation from the best plane of the four atoms = 0.025 Å). A –CH2—CH2– group in one ebthi ligand was disordered over two sites, with refined occupancy factors of 0.551 (6) and 0.449 (6). The asymmetric unit also contains a toluene solvent mol­ecule.

Tris[3,6-di-tert-butyl-1-(isoquinolin-1-yl)naphthalen-2-olato-κ2N,O]aluminium(III) toluene sesquisolvate

The central Al(III) atom of the title compound, [Al(C(27)H(28)NO)(3)]·1.5C(7)H(8), has octahedral geometry in which the three N atoms are arranged in a meridional fashion. One of the toluene solvent molecules is located on a general position, while the second is disordered around a centre of inversion. The ligand molecule has axial chirality, and two of the three ligands in the complex exhibit the same stereochemistry. The three independent chelate rings exhibit significantly different bite angles at the metal atom, with one [83.72 (8)°] notably smaller than the other two [87.22 (8) and 87.13 (8)°]. Calculation of the solid angle covered by the ligands at the metal atom reveals that coverage is greatest for the ligand group with the shortest Al-O bond distance.

Bis{2-[(4-chlorophenyl)iminomethyl]pyrrol-1-ido-κ2N,N′}bis(dimethylamido-κN)titanium(IV) toluene monosolvate

The mononuclear title compound, [Ti(C11H8ClN2)2(C2H6N)2]·C7H8, was synthesized by the reaction of N-(4-chloro­phen­yl)-2-pyrrolylcarbaldimine with Ti(C2H6N)4. The TiIV ion is situated on a twofold rotation axis and displays a distorted octa­hedral geometry defined by four N atoms from two 2-[(4-chloro­phen­yl)imino­meth­yl]pyrrol-1-ide ligands and two N atoms from two dimethyl­amine ligands. The Ti—Npyrrole bond length [2.1041 (19) Å] is longer than the Ti—Ndimethyl­amine bond length [1.9013 (19) Å]; the imine N atom exhibits the longest Ti—N bond [2.3152 (17) Å]. The toluene solvent mol­ecule is located on a twofold rotation axis running through the C atom of the methyl group. Consequently, the H atoms of the latter are rotationally disordered. The compound contains no markable hydrogen-bonding inter­actions.