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Twenty super-discotic liquid crystals based on a largely expanded [Formula: see text]-conjugated macrocycle of 1,4-diazatriphenylenocyaninato metal(II) complex, (abbreviated as (C[Formula: see text]O)[Formula: see text]TzM: M = Co(1), Ni(2), Cu(3), Zn(4); [Formula: see text] = 8(a), 10(b), 12(c), 14(d), 16(e)) were synthesized in order to investigate their mesomorphism and homeotropic alignment properties by using polarization microscopic observations, differential calorimetry, thermogravimetry, and temperature-variable X-ray diffraction. As a result, the (C[Formula: see text]O)[Formula: see text]TzCo and (C[Formula: see text]O)[Formula: see text]TzCu complexes with an odd number of [Formula: see text]-electrons in the central metal ions showed a tetragonal columnar (Col[Formula: see text] mesophase for [Formula: see text] = 8[Formula: see text]14, which exhibit spontaneous homeotropic alignment for a very wide temperature range from rt to the decomposition temperature at around 340[Formula: see text]C. On the other hand, the (C[Formula: see text]O)[Formula: see text]TzNi and (C[Formula: see text]O)[Formula: see text]TzZn complexes with an even number of [Formula: see text]-electrons in the central metal ions showed a rectangular columnar (Col[Formula: see text](P21/a[Formula: see text] mesophase for [Formula: see text] = 8[Formula: see text]16, which did not exhibit homeotropic alignment. As far as is known, such a unique parity effect of the number of [Formula: see text]-electrons on mesomorphism accompanied by homeotropic alignment has never been reported to date.

Two synthetizations of a novel series of phthalocyanine-based discotic liquid crystals substituted by a polymerizable group, acryloyl group or a norbornene group: 2-(12-acryloyloxydodecyloxy)-3-methoxy-9,10,16,17,23,24-hexakis (3,4-dialkoxyphenoxy)phthalocyaninato copper(II) [abbreviated as (n,12)PcCu(OCH[Formula: see text])(Acryloyl) (7: e ([Formula: see text] = 10), f ([Formula: see text] = 12), g ([Formula: see text] = 14))] and 2-(12-norborn-2-ene carbonyloxydodecyloxy)-3-methoxy-9,10,16,17,23,24-hexakis(3,4-dialkoxyphenoxy)-phthalocyaninato copper(II): [abbreviated as (n, 12)PcCu(OCH[Formula: see text])(Norb) (9e, f, g)]. Their liquid crystalline properties and homeotropic alignment were investigated using a polarizing microscope, a differential scanning calorimetry (DSC), and a temperature-variable X-ray diffractometer. As a result, each of the derivatives gave a Col[Formula: see text] mesophase in the higher temperature region, displaying perfect homeotropic alignment between the two glass plates. In order to obtain the thin film while keeping their homeotropic alignment at room temperature, attempts to polymerize the monomers, 7 and 9, in the Col[Formula: see text] phase showed homeotropic alignment. The polymerization of the acryloyl-substituted monomers (7) was not successful in any of the methods, whereas the polymerization of norbornene-substituted monomers (9) was quite successful by ring-opening metathesis polymerization with a Grubbs catalyst to obtain the novel polymers, poly-(n, 12)PcCu(OCH[Formula: see text])(Norb) (10e, f, g). Each of the polymers (10) were found to show a perfect homeotropic alignment from room temperature to ca. 200[Formula: see text]C of the decomposition temperature. Moreover, it was also revealed from temperature-variable small-angle X-ray diffraction studies that each of the polymers 10 showed a helical Col[Formula: see text] (helical tetragonal columnar) structure. The helical Col[Formula: see text] phase structure may be able for use in organic electroluminescent devices and solar cells in the future.

Three kinds of silicon phthalocyanine derivatives axially substituted by different groups were prepared and Singledecker-C[Formula: see text]PcSiCl2 (1a), Singledecker-C[Formula: see text]PcSi2(OH)4 (3a, b) and Doubledecker-(C[Formula: see text]PcSi)2Cl2 (4a, b) were obtained in order to investigate their mesomorphism for [Formula: see text] = 8 (a) and 12 (b). The mesomorphism was established by using polarizing microscopic observations, differential scanning calorimetric measurements, temperature-dependent electronic absorption spectra and temperature-dependent X-ray diffraction analysis. From the results, each of the derivatives, 1a, 3a, 3b, 4a and 4b showed columnar mesophases; 1a: Col[Formula: see text](P21/a), pseudo Col[Formula: see text] and Col[Formula: see text]; 3a, b: Col[Formula: see text](P21/a) and Col[Formula: see text]; 4a, b: two kinds of Col[Formula: see text]. Interestingly, each of the virgin samples of singledeckers, C8PcSiCl2 (1a), C8PcSi2(OH)4 (3a) and C8PcSi2(OH)4 (3a), were green in color but changed into blue over ca.180–190 [Formula: see text]C by polymerization. On the other hand, each of the double-deckers, (C[Formula: see text]PcSi)2Cl2derivatives (4a and 4b), decomposed over ca. 180–240[Formula: see text]C. Thus, the influence of the axial groups is so large on their mesomorphism that they exhibit unusual mesomorphic behaviors accompanied by color change.

We have synthesized a novel series of four flying-seed-like liquid crystals (1Ph-PhO)4PcM [5-M: M = Co (5-Co), Ni (5-Ni), Cu (5-Cu) and Zn (5-Zn)] which are based on a phthalocyanine core having peripheral bulky groups without long alkyl chains, in order to clarify the precise mechanism inducing their mesomorphism. For comparison, we have also synthesized a long alkyl-chain-substituted liquid crystal ([Formula: see text]C[Formula: see text]OPhO)8PcCu (7o) having the same phthalocyanine core with long alkyl chains in the periphery. Each of the derivatives 5-M and 7o showed a hexagonal ordered columnar (Colho) mesophase. Very interestingly, the halo positions in the X-ray diffraction patterns for the Colho mesophases of the flying-seed-like liquid crystals 5-M and the long alkyl-chain-substituted liquid crystal 7o were quite differently given at 5.7–6.2 Å and 4.6–4.7 Å, respectively. The halo positions of the representative derivatives 5-Cu and 7o having the same copper phthalocyanine (PcCu) core were finely measured at various temperatures by using the temperature-variable small angle X-ray diffraction technique. As the result, the derivatives 5-Cu and 7o showed sudden jumps of halo position from 5.5 to 5.7 Å and from 4.2 to 4.6 Å, respectively, at the phase transition from the crystalline phase to the liquid crystalline phase (Colho). This means that the volume changes ([Formula: see text]V) corresponding to these halo jumps originate from two different kinds of mechanisms by sudden free rotation of the bulky substituents and by sudden melting of the long alkyl chains. Thus, in this work we have unambiguously clarified these two different mechanisms inducing mesomorphism.

We have synthesized twelve novel discotic columnar liquid crystals based on a phenoxy-group-substituted phthalocyaninato copper(II) complex having the same alkoxy chain of C[Formula: see text]H[Formula: see text]O at different positions in the phenoxy group: the parent compounds {0a~0c-16}and the OH-substituted compounds {3a~3c-16}, the OFBA-substituted compounds {2a~2c-16}and the C[Formula: see text]-substituted dyads {1a~1c-16}. The letters of a, b and c mean substitution positions of C[Formula: see text]H[Formula: see text]O group at [Formula: see text], [Formula: see text] and [Formula: see text], respectively. We have investigated the influence of both substitution position of the alkoxy chains and the kind of terminal groups (OH, OFBA and C[Formula: see text] on the mesomorphism and the helical supramolecular structure, by using DSC, POM and temperature-variable small angle X-ray diffraction measurements. As a result, an additional big peak (Peak H) tends to appear at around 2[Formula: see text] = 1.1[Formula: see text] in the X-ray diffraction patterns only for the dyads {1a~1c-16}but not for the other compounds, {0a~0c-16}, {3a~3c-16}and {2a~2c-16}, regardless of the substitution positions of the alkoxy group. Moreover, we revealed that both the m-substituted derivative 1a-16 and the m,p-substituted derivative 1c-16 gave Peak H, but that only the p-substituted derivative 1b-16 did not give Peak H among these three dyads {1a~1c-16}. From the temperature-variable small angle X-ray diffraction measurements for the m,p-substituted derivative 1c-16 using two different sample preparation methods, we proved that the Peak H originates from a helical pitch of fullerenes. We also pointed out that the m-substituted long alkoxy chains are at least needed to form the helical supramolecular structure in the present (PhO)[Formula: see text]PcM-C[Formula: see text]-based dyads.

The formation of a metastable supercooled alkyl-π molecular liquid was prohibited by subtle alteration of the molecular structure., Metastable states of soft matters are extensively used in designing stimuli-responsive materials. However, the non-steady properties may obstruct consistent performance. Here we report an approach to eradicate the indistinguishable metastable supercooled state of functional molecular liquids (FMLs), which remains as a liquid for weeks or months before crystallizing, via rational molecular design. The phases (solid, kinetically stable liquid, and supercooled liquid) of a model FML, branched alkyl chain-substituted 9,10-diphenylanthracene (DPA), are found to be governed by subtle alterations of the molecular structure (alkyl-DPA ratio and bulkiness of the DPA unit). We thus outline molecular design principles to avoid supercooled FML formation. Moreover, we demonstrate a practical technique to rapidly discriminate supercooled FMLs (within 5 h) by accelerating their crystallization in differential scanning calorimetry heating via pre-annealing or relatively slow scanning.

A novel concept of composite-lattice-based liquid crystalline phases is presented in this article. The author explains and proves this concept from linear algebra and X-ray crystallography. When th...

The most difficult problem on syntheses of the phthalocyanine-based liquid crystals is the long reaction time. In order to shorten the reaction time, we have developed novel Methods A, B and D, for the syntheses of phthalocyanine-based liquid crystals by using microwave heating and/or adding a phase transfer catalysis of Aliquat 336. A series of phthalocyanine derivatives C[Formula: see text]PcZn(1) ([Formula: see text] 10, 12, 14, 16 and 18: a, b, c and e) could be successfully synthesized in a dramatically short reaction time of 30–60 min using Methods A and B by microwave heating. On the other hand, anothor series of the derivatives C[Formula: see text](OH)PcZn (2a–2e) could not be synthesized by microwave heating. Therefore, all these derivatives were synthesized using conventional Method C by oil bath heating, but the reaction took a very long time (22.5–88 h). To shorten the reaction time, we have developed Method D by oil bath heating with adding a phase transfer catalyst of Aliquat 336. In this method, we successfully shortened the reaction time from 88 h to 3 h for the synthesis of the derivative 2a. Thus, the reaction time for oil bath heating can be also greatly shortened by adding the phase transfer catalyst of Aliquat 336. Furthermore, we have established from POM, DSC and temperature-dependent X-ray diffraction measurements that the derivative C[Formula: see text]PcZn (1a) shows a very rare pseudohexagonal columnar (Col[Formula: see text] phase, and that the derivatives C[Formula: see text]PcZn (1b–1e) and C[Formula: see text](OH)PcZn (2b–2e) exhibit spontaneous perfect homeotropic alignment in a large area between two glass plates in their Col[Formula: see text] phases.

We have synthesized a series of six novel bis(β-diketonate)copper (II) complexes, 1a, 1b, 2a, 2b, 3a, and 3b, substituted by two bulky substituents in the short molecular axis direction to investigate their mesomorphism. The m,p,m'-trimethoxylphenyl-substituted derivatives, 2a and 2b, and the m,p-dimethoxylphenyl-substituted derivatives, 3a and 3b, did not show mesomorphism, whereas each of the p-methoxyphenyl-substituted derivatives 1a and 1b only showed a nematic phase, which was revealed from polarizing microscopic observations. We established from X-ray diffraction and Z-value calculations that each of the crank-like derivatives 1a and 1b forms a rectangular parallelepiped dimer and shows a biaxial nematic phase.

We have successfully synthesized a series of novel octakis([Formula: see text]-alkoxyphenylthio)phthalocyaninato copper(II) complexes, ([Formula: see text]-C[Formula: see text]OPhS)[Formula: see text]PcCu ([Formula: see text] = 2, 4, 6, 8, 10, 12, 14, 16: 1b~1i), by our developed method to reveal their mesomorphism. The phase transition behavior and mesophase structures have been established by using a polarizing optical microscope, a differential scanning calorimeter, and a temperature-dependent small angle X-ray diffractometer. Interestingly, the very short chain-substituted derivatives, ([Formula: see text]-C[Formula: see text]OPhS)[Formula: see text]PcCu (1a) and ([Formula: see text]-C[Formula: see text]OPhS)[Formula: see text]PCu (1b), show a hexagonal ordered columnar (Col[Formula: see text] mesophase, whereas each of the other longer-chain-substituted derivatives, ([Formula: see text]-C[Formula: see text]OPhS)[Formula: see text]PcCu ([Formula: see text] = 4~16: 1c~1i), shows only rectangular ordered columnar (Col[Formula: see text] mesophase(s). In contrast to the present longer-chain-substituted phenylthio derivatives, each of the previous longer-chain-substituted phenoxy derivatives, ([Formula: see text]-C[Formula: see text]OPhO)[Formula: see text]PcCu ([Formula: see text] = 10–20), shows a different columnar mesophase of Col[Formula: see text]. We discuss this difference of mesomorphism from the viewpoint of the different steric hindrance originated by the peripheral substituents, PhO and PhS groups. Moreover, we could estimate the optical band gaps of ([Formula: see text]-C[Formula: see text]OPhO)[Formula: see text]PcCu and ([Formula: see text]-C[Formula: see text]OPhS)[Formula: see text]PcCu (1f) from absorption edge of the Q-bands to be 1.79 eV and 1.70 eV, respectively. Therefore, the phenylthio-substituted derivative gave a narrower band gap byca. 0.1 eV in comparison with the phenoxy-substituted derivative.

Substitution of 1,3,6,8-tetraethynylpyrene with sterically bulky trimethylsilyl groups enabled four modes of molecular packing, two polymorphs (triclinic system (Y-form) and “loose” crystal Colho (OK-form)), a ”rigid” liquid crystalline phase Colho (OC-form), and an amorphous phase (OA-form), which emitted fluorescence at different wavelengths under UV light. The four phases could be interconverted by physical stimuli such as heating, grinding by mortar and pestle, and exposing to the vapor of organic solvents.

first published on 29 Jun 2017, We have synthesised a series of phthalocyanine-based discotic liquid crystals, (m-CnOPhO)(8)PcCu (n = 1-20: 2a-o), and investigated their mesomorphism by using a polarizing optical microscope (POM), a differential scanning calorimeter (DSC) and a temperature-dependent small angle X-ray diffractometer. We found that each of the derivatives 2a-o shows mesomorphism. However, the mesomorphism of the (m-CnOPhO)(8)PcCu derivatives strongly depends on the alkoxy chain length (n). The mesomorphism of the short chain-substituted derivatives 2a-e for n = 1-5 is a flying-seed-like type induced by flip-flop of the peripheral bulky substituents, whereas the mesomorphism of the long chain-substituted derivatives 2j-o for n = 10-20 is a conventional molten alkyl chain type induced by melting of the long alkyl chains. The moderately long chain derivatives (2f-i) for n = 6-9 in between show both types of mesophases. The detailed temperature-dependent X-ray diffraction measurements were carried out for three representative derivatives, 2b (n = 2 for n = 1-5), 2h (n = 8 for n = 6-9), and 2o (n = 20 for n = 10-20). As a result, we revealed that the Col(ro)(P2m) mesophase in 2b (n = 2) gave a halo denoted as Halo(arom). at d congruent to 5.2 angstrom due to flip-flop of the bulky aromatic substituents, and that the Colho mesophase in 2o (n = 20) gave a halo denoted as Halo(alkyl) at d congruent to 4.6-4.8 angstrom due to melting of the long alkyl chains. Therefore, we can distinguish the type of mesophase from Halo(arom). and Halo(alkyl). Very interestingly, the (m-C8OPhO)(8)PcCu (2h) derivative having moderately long alkyl chains gave Halo(alkyl) at about 4.8 angstrom in the lower temperature mesophase of Col(ho), but Halo(arom). at about 5.2 angstrom in the higher temperature mesophase of Col(ro)(P2(1)/a). This means that melting of the alkyl chains induces the Col(ho) phase in the lower temperature region, but that flip-flop of the bulky aromatic substituents induces the Col(ro)(P2(1)/a) phase in the higher temperature region. This unusual reverse phase transition sequence from a higher symmetry of the Col(h) mesophase to a lower symmetry of the Col(r) mesophase on a heating stage is attributable to such a unique stepwise melting of these two different types of substituents. To the best of our knowledge, this mesogen (2h) is the first example switching mesomorphism from the molten alkyl chain type to the flying-seed-like type in a discotic liquid crystal., Article, JOURNAL OF MATERIALS CHEMISTRY C. 5(29):7297-7306 (2017)

We have synthesized three novel octakis([Formula: see text]-chloropyridyloxy)phthalocyaninato copper(II) complexes, [x-PyO(m-Cl)][Formula: see text]PcCu([Formula: see text] [Formula: see text] 2, 3, 4: 2a–2c), keeping a chlorine atom at the meta position on the 2-, 3- and 4-pyridyloxy group, in which the nitrogen atom is located at the 2-, 3- and 4-positions, respectively. Their phase transition behavior and the mesophase structure have been established by using a polarizing optical microscope, a differential scanning calorimeter, and a temperature-dependent small angle X-ray diffractometer. Very interestingly, the mesomorphism appears with strong dependence of the position of nitrogen in [Formula: see text]-chloropyridyloxy group. The derivative [3-PyO(m-Cl)][Formula: see text]PcCu (2b) introduced a nitrogen atom at the 3-position is not mesogenic but crystalline. On the other hand, the derivative [2-PyO(m-Cl)][Formula: see text]PcCu (2a) introduced a nitrogen atom at the 2-position shows columnar mesomorphism only at very high temperatures over 325°C. The derivative [4-PyO(m-Cl)][Formula: see text]PcCu (2c) introduced a nitrogen atom at the 4-position shows columnar mesomorphism in a very wide temperature region from rt to the decomposition temperature at 306°C. From the viewpoint of N…Cl halogen bond, we have discussed about relationship between their mesomorphism and the position of nitrogen atom in [Formula: see text]-chloropyridyloxy group.

We have synthesized a novel liquid crystalline phthalocyanine(Pc)-fullerene(C-60) dyad (C14S)(6)PcCu-VAN-C-60 (3a) bridged by an inexpensive natural product of vanillin (VAN), instead of the previous long n-alkylene chain spacer. We have also synthesized a comparative dyad (C14S)(6)PcCu-OPh-C-60 (3b) bridged by p-hydroxybenzaldehyde (OPh), in order to investigate the influence of the methoxy group in the vanillin moiety on homeotropic alignment between two glass plates. Very interestingly, homeotropic alignment could be observed only for the dyad (C14S)(6)PcCu-VAN-C60 (3a) having a methoxy group in the vanillin moiety, whereas it could not be observed for the dyad (C14S)(6)PcCu-OPh-C-60 (3b) having no methoxy group at the phenoxy group. It is very noteworthy that such a slight difference in these molecular structures between 3a and 3b becomes a crucial point to show the homeotropic alignment. Each of the dyads, 3a and 3b, showed two hexagonal ordered columnar (Col(ho)) mesophases. Each of the Col(ho) mesophases in 3a and 3b gave an additional very strong reflection peak named as Peak H in a very low angle region of the SAXS (small angle X-ray scattering) pattern. Peak H could be established, from two different SAXS measurement methods, as one pitch in a helical structure of the fullerenes around the Pc column., Article, JOURNAL OF PORPHYRINS AND PHTHALOCYANINES. 20(12):1444-1456 (2016)

Diels–Alder reaction of cyclic biphenylylene–acetylene compound 3 with tetraphenylcyclopentadienone (5) realized the preparation of large-sized cyclic polyphenylene array 4. This is the first example of a cyclic polyphenylene array with a complete ring arrangement of a chiral-type CNT segment with (12,3)-structure. Transformation of 4 to the chiral-type CNT segment was attempted, but resulted in the formation of a complicated mixture probably due to the partial dehydrogenation and/or the partial elimination about the long alkyl chains. Rather efficient blue emission of the cyclic compounds 3 and 4 was discussed utilizing fluorescence quantum efficiencies and lifetimes both in their solid state and in their solution. By thermal analyses triple-melting behavior of 3 was clarified.

We have synthesized two novel phthalocyanines, (m-SF5PhO)(8)PcCu (7b) and (p-SF5PhO)(8)PcCu (7c), in order to investigate their flying-seed-like mesomorphism. Their phase transition behavior and the mesophase structure have been established by using a polarizing optical microscope, a differential scanning calorimeter, and a temperature-dependent small angle X-ray diffractometer. Very interestingly, the derivative (m-SF5PhO)(8)PcCu (7b) substituted a SF 5 group at m-position showed a Col(10)(P2(1)/a) (= p2gg) mesophase from rt to 315.0 degrees C, whereas the derivative (p-SF5PhO)(8)PcCu (7c) substituted a SF 5 group at p-position showed a crystalline (K) phase from rt to the decomposition temperature at ca. 336 degrees C without showing mesomorphism. Thus, the novel phthalocyanine derivative (m-SF5PhO)(8)PcCu (7b) substituted a strong electron withdrawing SF 5 group at m-position shows only one columnar mesophase in a very wide temperature region from rt to 315.0 degrees C. Furthermore, the Q-band wavelengths (672.2 and 672.1 nm) of the present (m-SF5PhO)(8)PcCu (7b) and (p-SF5PhO)(8)PcCu (7c) are shorter than that (680.3 nm) of the previous [(m-C-1) PhO](8)PcCu (5c) derivative. It can be attributed to strong electron withdrawing nature of the SF5 group on the phenoxy group., Article, JOURNAL OF PORPHYRINS AND PHTHALOCYANINES. 20(7):822-832 (2016)

The spontaneous organization of two‐dimensional polyaromatic molecules into well‐defined nanostructures through noncovalent interactions is important in the development of organic‐based electronic and optoelectronic devices. Two regioisomers of thiophene‐fused zinc naphthalocyanines ZnTNcendo and ZnTNcexo have been designed and synthesized to obtain photo‐ and electroactive liquid crystalline materials. Both compounds exhibited liquid crystalline behavior over a wide temperature range through intermolecular π–π interactions and local phase segregation between the aromatic cores and peripheral side chains. The structural differences between ZnTNcendo and ZnTNcexo affected the stacking mode in self‐assembled columns, as well as symmetry of the two‐dimensional rectangular columnar lattice. The columnar structure in liquid crystalline phase exhibited an ambipolar charge‐transport behavior.

Highly viscous phthalocyanine-based molecular liquids 1 and 2 exhibited stimuli-responsive rheological properties in response to the changes of temperature and shear force.

A homologous series of the phthalocyanine-fullerene dyads, (CnS)6PcCu-Cm-C60 (4a~g) [(n, m) = (14, 8) (a); (14, 10) (b); (14, 12) (c); (16, 8) (d); (16, 10) (e); (16, 12) (f); (18, 10) (g)], have been synthesized with changing both the chain length of the peripheral alkylthio group (n) and the spacer length (m) between Pc and C60 in order to find out the homologues showing perfect homeotropic alignment at rt. As a result, each of the dyads 4a~g shows perfect homeotropic alignment in their hexagonal ordered columnar (Colho) mesophases and the homologues 4a~c having shorter alylthio chains (n = 14) show perfect homeotropic alignment at rt. Very interestingly, the spherical C60 parts form a helical structure around the column formed by the disk-like Pc parts. This supramolecular structure very resembles spiranthes flower. The spiranthes-like supramolecular structure is compatible with one-dimensional nano-array expecting the high conversion efficiency of solar cells.

We synthesized a novel series of flying-seed-like derivatives (3a–g) based on phthalocyaninato copper(II) (abbreviated as PcCu) substituted by bulky groups {PhO (a), (o-C1)PhO (b), (m-C1)PhO (c), (p-C1)PhO (d), [m,p-(C1)2]PhO (e), [m,m′-(C1)2]PhO (f), and [m,p,m′-(C1)3]PhO (g)} instead of using long alkyl chains, in order to investigate their mesomorphism. Their phase transition behaviour and the mesophase structures were established using a polarizing optical microscope, a differential scanning calorimeter, a thermogravimetry analyser and a temperature-dependent small angle X-ray diffractometer. It was demonstrated that (PhO)8PcCu (3a) and [(p-C1)PhO]8PcCu (3d) show no mesophase, whereas [(m-C1)PhO]8PcCu (3c), {[m,p-(C1)2]PhO}8PcCu (3e), {[m,m′-(C1)2]PhO}8PcCu (3f), and {[m,p,m′-(C1)3]PhO}8PcCu (3g) show various kinds of columnar mesophases of Colro(P21/a), Colro(P21/a), Colro(C2/m) and Coltet.o, respectively, while [(o-C1)PhO]8PcCu (3b) shows a monotropic Colro(P2m) mesophase. Thus, we revealed that mesomorphism could be induced by these novel bulky substituents instead of using long alkyl chains, and that the mesophase structures were greatly affected by the number and position of the methoxy groups. In particular, it is very interesting that the derivatives with methoxy group(s) at the meta position(s), namely, 3c, 3e, 3f and 3g, tend to show enantiotropic mesophase(s), whereas neither the derivative with no methoxy group, 3a, nor the derivative with a methoxy group at the para position, 3d, show a mesophase.

Luminescent lanthanide (Tb3+, Eu3+) complexes were prepared by reaction of Tb3+ or Eu3+ with dendritic amphiphile (3,4,5-tris(dodecyloxy)benzoate), then their liquid crystalline and luminescent behavior were studied. The complexes exhibited thermotropic liquid crystalline mesophases with columnar hexagonal structure. The complexes emitted the characteristic luminescence of the core metals. Additionally, in the Eu3+ complex, the ratio of the intensity of 614 nm to the intensity of 585 nm (I614/I585) remarkably decreased around the transition temperature from crystal to mesophase, suggesting that the coordination environment of Eu3+ gets more symmetrical due to the phase transition.

We have synthesized a novel type of donor–acceptor liquid crystalline material, phthalocyanine-fullerene ( Pc - C 60) dyad, [m,p,m′-( C 14 O )3 PhO ]6 PcCu - C 60 (7), and the Pc precursors, [m,p,m′-( C 14 O )3 PhO ]6 PcCu - OFBA (6) and [m,p,m′-( C 14 O )3 PhO ]6 PcCu - OH (5), and established their mesomorphism by using a polarizing optical microscope, a differential scanning calorimeter and a small angle X-ray diffractometer. Very interestingly, their corresponding previous parent Pc derivative, [m,p,m′-( C 14 O )3 PhO ]8 PcCu (4), shows a very wide temperature region ca. 90°C of a bicontinuous Cub(Pn3m) mesophase, whereas the present children Pc precursors (5 and 6) and Pc- C 60 dyad 7 show not the Cub mesophase but a Colho mesophase. It is also noteworthy that the staking distance in the Colho mesophase of the Pc- C 60 dyad 7was a very big value of ca. 9.1 Å, which is the biggest in discotic liquid crystals to our best knowledge. It may be originated from the biggest excluded volume caused by thermal fluctuation of peripheral long alkoxy chains at m, m′-positions. The excluded volume caused by thermal fluctuation of the peripheral long chains is so big that the molecular shape of the Pc derivative 4 and the Pc- C 60 dyad 7 very resembles a flat pumpkin.

We have synthesized novel liquid crystalline Pc - C 60 dyads (CnS)6PcCu-C60 (n = 14, 16, 18: 1a–1c) by using our developed synthetic method in order to investigate the mesomorphism and alignment behavior. Each of the (CnS)6PcCu-C60 dyads shows perfect homeotropic alignment in the Colho mesophase between two glass plates for n = 14, 16, 18 and also on a glass plate for n = 14, although none of the parent Pc compounds (CnS)8PcCu and the Pc precursors (CnS)6PcCu-OH and (CnS)6PcCu-OFBA shows homeotropic alignment. It may be attributed to the strong affinity between fullerene and glass surface. Although the reason is not so clear at the present time, this is very useful guideline for the molecular design to prepare homeotropic alignment-showing discotic liquid crystals. Very interestingly, the spherical C 60 parts form a helical structure around the column formed by the disk-like Pc parts This supramolecular structure very resembles spiranthes. The spiranthes-like supramolecular structure is compatible with one-dimensional nano-array expecting the high conversion efficiency of solar cells.

A homologous series of the phthalocyanine-fullerene dyads, C-n-PcM(OFbaC60) (n = 6, 8, 10, 12; M = Cu, Ni, Co: 3a-3f), have been synthesized to obtain homeotropic alignment at rt and investigate the effects of spacer chain length (n = 6, 8, 10, 12) and central metal (M = Cu, Ni, Co) on the mesomorphism. Interestingly, the shorter-spacer-substituted (n = 6, 8; M = Cu) dyads 3a and 3b showed a hexagonal columnar mesophase (Col(h)), whereas the longer-spacer-substituted (n = 10, 12; M = Cu, Ni, Co) dyads 3c-3f showed a tetragonal columnar mesophase (Col(tet)). Moreover, each of the homologs 3a-3e shows perfect homeotropic alignment in both the Col(h) and Col(tet) mesophases at rt. More interestingly, these columnar mesophases gave a very unique XRD reflection peak denoted as Peak H in a very small angle region of 0.8 < 2 theta < 2.0 degree. We have established at the first time from our developed two new XRD sample preparation techniques that the Peak H is due to the helical structure of fullerenes around columns formed by one-dimensionally stacked Pc cores. 1D nano array structure of donor and acceptor between two electrodes is recently proposed to obtain higher photoelectric conversion efficiency for organic thin film solar cells. This 1D nano array structure is almost compatible with the present homeotropically aligned Pc-C-60 dyads 3a-3f between two glass plates. Hence, these novel Pc-C-60 dyads 3a-3f may be very suitable to organic thin film solar cells., Article, JOURNAL OF PORPHYRINS AND PHTHALOCYANINES. 17(11):1080-1093 (2013)

Modified 3,5-dipyrrolylpyrazole (DPP) derivatives in their protonated form produce planar [2+2]-type complexes with trifluoroacetate (TFA) ions. These complexes serve as constituent components of ion-pair-based assemblies. An essential strategy for the construction of dimension-controlled organized structures based on these [2+2]-type complexes is the introduction of aryl rings bearing long alkyl chains, which enables the formation of 2D patterns at interfaces, supramolecular gels, and mesophases.

In our previous work, we could successfully synthesize the 1:1 phthalocyanine-fullerene (Pc-C-60) dyads, (OFbaC(60))PcCu(OCH3) 2, in very high yields (81 similar to 96%) by using Prato reaction. In this study, we have prepared novel Pc-C-60 dyads, (OFbaC(60)) PcM (M = Co (a), Ni (b), Cu (c), metal free (d)) 3a-3d without the methoxy group. The target Pc-C-60 dyads 3a-3d could be successfully synthesized in good yields also by Prato reaction. It is surprising for us that removal of a very small methoxy group from the big (OFbaC(60))PcCu(OCH3) molecule (2) significantly lowers the cp of (OFbaC(60))PcCu (3c) by about 70 degrees C in comparison with that of 2 having the methoxy group. Very interestingly, each of the novel dyads 3a-3d synthesized here shows perfect homeotropic alignment in the tetragonal columnar phase (Col(tet)). Moreover, it is noteworthy that 3c and 3d show only one Col(tet.o) mesophase having ordered stacking distance with perfect homeotropic alignment. Such simple phase transition can contribute to maintain stable performance in wide temperature range, when they will be applied to organic thin film solar cells., Article, JOURNAL OF PORPHYRINS AND PHTHALOCYANINES. 17(4):264-282 (2013)

In previous work, we successfully synthesized the first columnar liquid crystalline 1:1 phthalocyanine(Pc)-fullerene( C60 ) dyad, C12(OMalC60)PcCu (4), showing spontaneous homeotropic alignment, by using Bingel reaction. However, it gave undesirable 2:1 and 3:1 Pc- C60 by-products at the same time, so that the 1:1 Pc- C60 dyad (4) could be obtained in a very low yield (20%). On the other hand, in this work we have prepared novel Pc- C60 dyads, C12(OFbaC60)PcM (8: M = Co (a), Ni (b) and Cu (c)), by using Prato reaction. Very interestingly, it gave almost only the target 1:1 Pc- C60 dyads 8a–8c in very high yields (81–96%) with negligible amount of Pc- C60 by-products. These dyads 8a–8c and the precursor Pc derivatives were characterized by polarizing microscope, differential scanning calorimeter and temperature-dependent X-ray diffractometer. Thus, it was revealed that each of the dyads and precursors shows spontaneous homeotropic alignment in their Coltet mesophase.

We synthesized a novel discotic liquid crystalline compound, octakis[3-(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)phenoxy]phthalocyaninato copper(II) (abbreviated as [m- MeO(EtO)3PhO]8PcCu ), and established the mesomorphism by using a differential scanning calorimeter, a polarizing optical microscope, and temperature-dependent wide angle X-ray diffraction diffractometer. Very interestingly, this [m- MeO(EtO)3PhO]8PcCu complex showed a hexagonal ordered columnar (Colho) mesophase in the virgin sample, whereas it showed a rectangular ordered columnar (Colro(P21/a)) mesophase in the non-virgin sample. The Colho mesophase gave a dimer stacking distance at 9.26 Å, whereas the Colro mesophase gave a short monomer stacking distance at 3.45 Å. Furthermore, this novel Pc derivative is readily soluble in polar solvents such as acetone, ethanol and methanol. Using antagonist solubilities of the present hydrophilic [m- MeO(EtO)3PhO]8PcCu derivative in a polar solvent and the previous hydrophobic (C10O)16TzCu derivative in the non-polar solvent, a p-n junction layered thin films could be successfully prepared.

We have synthesized novel hexaphenoxy-substituted phthalocyanine derivatives, 2-(12-hydroxydodecyloxy)-3-methoxy-9,10,16,17,23,24-hexakis(3,4-di-n-alkoxyphenoxy)phthalocyaninato copper(II) (abbreviated as Cn(OC12OH)PcCu : n = 10, 12, 14), and investigated their columnar mesomorphism and homeotropic alignment property. These hexaphenoxy-substituted Pc derivatives could be successfully isolated and purified from the mixture products by polarity difference. It was revealed by using polarizing optical microscopic observations, differential scanning calorimetry and temperature-dependent X-ray diffraction studies that each of the hexaphenoxy-substituted Pc derivatives has plural mesophases, and that the tetragonal columnar (Coltet) mesophase shows spontaneous perfect homeotropic alignment between two non-surface-treated glass plates without any defects and polydomain boundaries.

We have synthesized 34 novel homologous discotic liquid crystals, octakis(m-alkoxyphenoxy)phthalocyaninato metal(II) {abbreviated as (m- CnOPhO)8PcM (M = Co(1), Ni(2), Cu(3), Zn(4) and H2 (5); n = 8(a), 10(b), 12(c), 14(d), 16(e), 18(f) and 20(g))}, and investigated parity effect of the number of d-electrons on the stacking distances in their columnar mesophases. It was revealed from temperature-dependent wide angle X-ray diffraction studies that each of the cobalt(II) (d7) complexes (1a–1g) and the copper(II) (d9) complexes (3b–3g) showed a single hexagonal ordered columnar (Colho) mesophase with a very short stacking distance at 3.3 Å, and that the nickel(II) (d8) complexes (2a–2g) and the metal-free (d0) derivatives (5a–5g) showed a single pseudo-hexagonal ordered columnar (Colrho) mesophase with a little bit longer stacking distances at 3.4 Å. Very interestingly, the nickel complex (2a) and metal-free derivatives (5a–5c) gave an extremely big (001) reflection peak with the second (002) reflection peak. Furthermore, the zinc(II) (d10) complexes (4a–4g) showed two different rectangular ordered columnar mesophases, Colro(P2/m) and Colro(P21/a), with a little bit longer stacking distance at 3.4 Å. Thus, the shorter stacking distance, 3.3 Å, appeared for the odd number of d-electrons, whereas the longer stacking distance, 3.4 Å, appeared for the even number of d-electrons. Hence, the stacking distances depend on parity of the number of d-electrons in the central metal(II). To our best knowledge, it is the first example of parity effect on the stacking distances in columnar mesophases.

A series of square planar platinum(II) salen complexes containing 4-substituted alkoxy chains of aromatic rings, [Pt((4-CnH2n+1O)2salen)] (n = 3 (1), 4 (2), 6 (3), 8 (4), 10 (5), 12 (6), 14 (7), 16 (8), and 18 (9)) has been prepared, and photophysical and mesomorphic properties have been investigated. Complexes 1–9 emitted intense phosphorescence from the mixed exited-state between the MLCT (MLCT = metal-to-ligand charge transfer) and LLCT (LLCT = ligand-to-ligand charge transfer) states both in dichloromethane solution and in solid states at room temperature. The red-shifted solid-state emission spectra from monomers in solution are caused by the supramolecular contact with one-dimensional stacking between neighboring chromophores (salen moieties) through the weak C–H⋯O type hydrogen bonding and van der Waals interactions in the solid state revealed by an X-ray crystallographic analysis for 2. Though 1–4 did not exhibit any mesophases (liquid–crystalline phases), 5–9 showed a lamello-columnar (ColL) mesophase with the high thermal stability, leading to the different phosphorescence spectra from both in solution and in solid states. This is affiliated with the appearance of the intermolecular d z 2 Pt ( II ) - d z 2 Pt ( II ) orbital interaction in a one-dimensional stacking distance with ca. 3.0 A due to self-assemblies in the liquid crystal which gives rise to the MMLCT (MMLCT = metal–metal-to-ligand charge transfer) transition. This is supported by absorption and emission measurements in the wide range from room temperature in the solid state to the clearing points (around 280 °C). The relationship between molecular assemblies and photophysical properties is discussed.

The racemic oxovanadium(IV) salmmen complexes, [VO((rac)-(4-X-salmmen))] (X = C12C10C5 (1), C16 (2) and C18 (3); salmmen = N,N′-monomethylenebis-salicylideneimine) with “banana shaped” molecular structures were synthesized and their ferroelectric properties were investigated. These complexes exhibit well-defined hysteresis loops in their viscous phases, moreover, 1 also displays liquid crystal behaviour. We observed a synergetic effect influenced by three structural aspects; the methyl substituents on the ethylene backbone, the banana shaped structure and the square pyramidal metal cores all play an important role in generating the observed ferroelectricity, pointing the way to a useful strategy for the creation of advanced ferroelectric soft materials.

Hexakis(6-hexadecyl-2-azulenyl)benzene (1b) has been synthesized by Co2(CO)8-catalyzed cyclotrimerization reaction of bis(6-hexadecyl-2-azulenyl)acetylene (2b). The mesomorphic behaviors of 1b, 2b, and 6-hexadecyl-2-phenylazulene (3b) were studied by differential scanning calorimetry (DSC), polarizing optical microscopy (POM), and X-ray diffraction (XRD) techniques and their mesomorphic properties were compared with those of their 6-octyl derivatives 1a, 2a, and 3a. Increase of the number of carbon atoms in the peripheral side chains drops the isotropization temperatures of 1b, 2b, and 3b by 56.9 °C, 33 °C, and 23.6 °C, respectively. Additionally, the phase-transition behavior varied with increase of the number of the peripheral chains, as well as decrease of the crystalline–mesophase transition temperatures, except for compound 3b. As the results, spontaneous monodomain homeotropic molecular alignment was revealed by compound 1b in its Colhd mesophase on non-treated glass substrate, which would be attracted to the application for the device fabrication of molecular materials.

We succeeded in the development of two facile synthetic methods of carbon nanotubes (CNTs) by using a domestic microwave oven and a commercially available small microwave furnace from Art Box™. Our...

We have developed a novel synthetic method that enables us to easily synthesize metal-capsulated carbon nanotubes (CNTs) in a laboratory by using a combined technology of electrospinning-metallization and microwave heating. These techniques greatly shorten the time for the synthesis of the CNTs in comparison with the conventional methods. TEM analysis confirmed a successful formation of the CNTs, and the resulting CNTs were multi-walled and found to be about 25–100 nm in diameters. The products prepared by heating at 600 and 900°C exhibited less-developed and strongly curved CNTs, whereas the products prepared by heating at 700 and 800°C relatively well-developed long CNTs. Copyright © 2010 John Wiley & Sons, Ltd.

We found in our previous works that the sandwich-type phthalocyanine-based rare earth metal complexes, bis[2,3,9,10,16,17,23,24-octakis(3,4-dialkoxyphenoxy)phthalocyaninato]lanthanoid(III) ({[( C n O )2 PhO ]8 Pc }2 M, M = Eu and Lu , n = 8–16) (1 and 3), exhibited two thermotropic cubic mesophases, Cub1 and Cub2, together with columnar mesophases. It is rare that the discotic liquid crystalline compounds show the cubic mesophase. We revealed that their symmetries of the lower temperature Cub1 mesophase and the higher temperature Cub2 mesophase were [Formula: see text] and [Formula: see text], respectively. However, their detailed phase structures were not revealed in the previous works. In this work, we have synthesized a series of novel sandwich-type phthalocyanine-based terbium complexes, bis[2,3,9,10,16,17,23,24-octakis(3,4-dialkoxyphenoxy)phthalocyaninato]terbium(III) ({[( C n O )2 PhO ]8 Pc }2 Tb , n = 8–16) (2). Their mesomorphic properties have been investigated using polarization microscope, DSC and temperature-dependent X-ray diffraction techniques. As the result, the present Tb complexes (2) also showed two cubic mesophases, [Formula: see text] and [Formula: see text], together with columnar mesophases, as well as the previous Eu homologs (1) and Lu homologs (3). We have furthermore investigated by using temperature-dependent electronic absorption spectroscopy to reveal their detailed phase structures and phase transition mechanism of these two Cub mesophases. We have revealed that the [Formula: see text] mesophase forms a bicontinuous structure consisting of branched columns like jungle gym, but that the [Formula: see text] mesophase forms a discontinuous structure consisting of short columns like drums that resulted from the cutting off of the branched columns.

We have synthesised two novel series of octaphenoxyphthalocyaninato copper(II) complexes, (m-C n O)PcCu (n = 2–10: 2b–f), and bis(octaphenoxyphthalocyaninato)terbium(III) complexes, [(m-C n O)Pc]2Tb (n = 2–10: 3b–f), which were substituted by dodecyloxy chains at the p-positions in the phenoxy groups and various length of alkoxy chains at the m-positions in the phenoxy groups. Their mesomorphic properties were investigated by polarising microscopy, differential scanning calorimetry (DSC) and temperature-dependent X-ray diffraction techniques. The Cu complex (2b) and the Tb complexes (3b–d), having shorter chains at the m-positions in the phenoxy groups, exhibited a lamellocolumnar (ColL) mesophase. Moreover, it was revealed that the complexes (2 and 3) tend to change their mesophases of the order of Colh → ColL → Colr → Cub → Coltet with elongating the length of the alkoxy chains at the m-positions. †Reference [1].

It has long been believed that the phase transition behavior and clearing points (c.p.s.) of phthalocyanine-based metallomesogens scarcely change regardless of the kind of central metal. In this work, we have synthesized a series of novel sandwich-type phthalocyanine-based lanthanoid complexes, bis[2,3,9,10,16,17,23,24-octakis(3,4-didodecyloxyphenoxy)phthalocyaninato]lanthanoid(III) (abbreviated as {[(C12O)2PhO]8Pc}2M, M = La, Ce, Eu, Gd, Tb, Yb and Lu : 1–7). Their mesomorphic properties were investigated by polarization microscope, DSC and temperature-dependent X-ray diffraction techniques to compare with the phase transition behavior and c.p.s. of the complexes. Very interestingly, the c.p.s. of these seven rare-earth metal complexes increased in an order of La (1) → Ce (2) → Eu (3), reached to a maximum for Gd (4), and decreased in an order of Tb (5) → Yb (6) → Lu (7). We have noticed that their rise and fall of c.p.s. correspond to the values of total spin quantum number (S) of the central rare-earth metal ions. Thus, it was found, for the first time in metallomesogens, that the S values of central rare-earth metal ions strongly influence their c.p.s.

The metal complexes with long alkyl chains [Co(C16-terpy) 3 ](BF 4 ) 2 ( 1 ) and [Fe(C16-terpy) 2 ](BF 4 ) 2 ( 2 ) were synthesized and the physical properties of the complex were characterized by magnetic susceptibility, Mossbauer spectroscopy, polarizing optical microscopy, differential scanning calorimetry, and X-ray scattering, where C16-terpy is 4′-hexadecyloxy-2,2′:6′,2′′-terpyridine. Variable-temperature magnetic susceptibility measurements and/or Mossbauer studies revealed that the complex 1 exhibited unique spin transition ( T 1/2 ↓ = 217 K and T 1/2 ↑ = 260 K) induced by structural phase transition, and the complex 2 was in the low-spin state in the temperature region of 5–400 K before the first mesophase transition. The cobalt(II) and iron(II) complexes exhibited liquid-crystal properties in the temperature range of 371–528 K and 466–556 K, respectively. After mesophase transition, the complex 1 exhibited only slight spin transition ( T 1/2 ↓ = 266 K and T 1/2 ↑ = 279 K), and the complex 2 was in the low-spin state. The compounds with multifunction, i.e., magnetic property and liquid-crystal properties, are important in the development of molecular materials.

The silver ion–based supramolecular adducts bearing long alkyl chains (Cn-Phen: n (carbon number of alkyl chain) = 12, 14, 16, 18) were prepared by reaction of phenazine and silver alkylsulfonates. Their liquid crystalline behavior was studied by differential scanning calorimetry, polarizing microscopy, and temperature-dependent X-ray diffraction techniques. Each of the adducts exhibits three mesophases with layer structures; an unidentified smectic phase (Sx), smectic C (SC), and smectic A (SA) phases. Furthermore, it was found that each of the layers has a two-dimensional silver ion sheet sandwiched above and below by two aliphatic sheets.

Metal complexes with long alkyl chains [Co(C16-terpy)3](BF4)2 (1), [Fe(C16-terpy)2](BF4)2 (2), [Co(C16-terpy)2](BPh4)2 (3), [Co(C14-terpy)2](BF4)2 (4), and [Fe(C12C10C5-terpy)2](BF4)2 (5) were synthesized and their physical properties characterized, where C16-terpy, C14-terpy, and C12C10C5-terpy are 4′-hexadecyloxy-2,2′:6′,2′′-terpyridine, 4′-tetradecyloxy-2,2′:6′,2′′-terpyridine, and 4′-5′′′-decyl-1′′′-heptadecyloxy-2,2′:6′,2″-terpyridine, respectively. Complexes 1, 2, and 5 exhibited liquid–crystal properties in the temperature ranges of 371–528 K and 466–556 K, and 88–523 K, respectively. Variable-temperature magnetic susceptibility measurements revealed that the Co(II) complexes 1 and 4 exhibited unique spin transitions (T 1/2↓ = 217 K and T 1/2↑ = 260 K for 1 and T 1/2↓ = 250 K and T 1/2↑ = 307 K for 4), so-called ‘reverse spin transition,’ induced by structural phase transitions. Complex 3 exhibited gradual spin-crossover behavior (T 1/2 = 160 K.), and complex 5 exhibited spin transitions (T 1/2↑ = 288 K and T 1/2↓ = 284 K) at the liquid crystal transition temperature. Compounds with multifunction, i.e., magnetic and liquid–crystal properties, are important in the development of molecular materials.

It has long been believed that the phase transition behavior and clearing points (c.p.s) of phthalocyanine-based metallomesogens scarcely change regardless of the kind of central metal. In this work, we have synthesized a series of novel sandwich-type, europium complexes, bis[2,3,9,10,16,17,23,24-octakis(3,4-dialkoxyphenoxy)phthalocyaninato]europium(III) (abbreviated as {[( C n O )2 PhO ]8 Pc } 2 Eu (n = 8-16) (2a–2i)). Their mesomorphic properties were investigated by polarization microscope, differential scanning calorimeter and temperature dependent X-ray diffraction techniques to make a comparison with the phase transition behavior and c.p.s of the previously reported lutetium homologs ({[( C n O )2 PhO ]8 Pc }2 Lu (n = 8-16) (1). Very interestingly, the c.p.s of {[( C n O )2 PhO ]8 Pc }2 Eu complexes (2) are higher by 35–61°C than those of {[( C n O )2 PhO ]8 Pc }2 Lu complexes (1) having the same chain length (n). Furthermore, these Eu complexes (2) exhibited unique double-clearing behavior, whereas the Lu complexes (1) did not. For instance, the Eu complex (2i: n = 16) exhibited the following phase transition sequence: crystalline phase (K) 49°C Colh 133°C [Formula: see text] 158°C [Formula: see text] 216°C I.L.; the I.L. very slowly transformed into a Coltet mesophase; on further heating, Coltet cleared into I.L. again at 240°C. On the other hand, the corresponding Lu complex (1i: n = 16) exhibited a phase transition sequence of K 50°C Colh 124°C [Formula: see text] 148°C Coltet 205°C I.L., and did not exhibit the doubleclearing behavior. Thus, it was revealed for the first time, in the phthalocyanine-based metallomesogens, that the central metal had a large influence on their c.p.s and their phase transition behavior.

A series of sandwich-type metal complexes, bis[2,3,9,10,16,17,23,24-octakis(3,4-dialkoxyphenoxy)phthalocyaninato]lutetium(III) ({[( C n O )2 PhO ]8 Pc }2 Lu (n = 8−16): double-deckers (2)), were synthesized. As the by-product, tris[2,3,9,10,16,17,23,24-octakis(3,4-diakoxyphenoxy)phthalocyaninato]dilutetium(III) ({[( C n O )2 PhO ]8 Pc }3 Lu 2 (n = 8, 9, 11, 12, 14, 16): triple-deckers (3)) were successfully separated. The mesomorphic properties of these double-deckers (2) and triple-deckers (3) were investigated using a polarization microscope, differential scanning calorimetry and temperature-dependent X-ray diffraction techniques. The double-deckers (2) showed Colh , Cub and Coltet mesophases for n ≥ 10. On the other hand, the triple-deckers (3) showed only a Colr mesophase for n = 8, only a Coltet mesophase for n = 14, and both Colr and Coltet mesophases for n = 9, 11, 12 and 16. For the Coltet mesophase, both the double-deckers (2) and the triple-deckers (3) exhibited spontaneous homeotropic alignment in a large area. In comparison with the homeotropic alignment of these present lutetium complexes 2, 3 and the previous copper complexes, 2,3,9,10,16,17,23,24-octakis(3,4-dialkoxyphenoxy)phthalocyaninato copper(II) ([( C n O )2 PhO ]8 PcCu (n = 9-14): single-decker (1)), the alignment was fast, slow and fast, respectively, in the order of the single-deckers (1), double-deckers (2) and triple-deckers (3). Very interestingly, the complexes 1 and 3 which have flat Pc macrocycles gave fast alignment, whereas the complexes, 2, which have non-flat Pc macrocycles, gave slow alignment. Thus, it was revealed for the first time that the flatness of discotic liquid crystalline molecules influences the speed of homeotropic alignment.

The silver-ion-based supramolecular adducts bearing long alkyl chains were prepared by reaction of pyridazine and silver alkylsulfonates. The-liquid crystalline behavior of the adducts was studied by differential scanning calorimetry, polarizing microscopy, temperature-dependent IR, and temperature-dependent X-ray diffraction. Each of the adducts exhibits two rectangular columnar mesophases having P2/a symmetry and has a strong tendency of parallel alignment of the alkyl chains orientating toward the surface of the glass substrate.