We investigated the self-assembled structure of alkoxy- and N-alkylcarbamoyl-substituted porphyrin at the solid–liquid interface by using STM. The alkoxy porphyrin showed phase transition from face-on to edge-on orderings. The phase transition requires the close packed structure of alkoxy porphyrin. By changing the side chain to N-alkylcarbamoyl groups, persistent edge-on orderings were constructed. The edge-on structure was had the Moiré patterns by the interference to HOPG underneath, which revealed the precise intermolecular distance between porphyrins.

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A novel metal-organic gel is formed by mixing of N-acetylaspartic acid, DABCO and Cu(NO3)2 in DMF. In addition, the gelation property depended on the organic solvent, amine and transition metal ions.

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It is known that Eu3+ ion shows very strong red fluorescence by forming the complex using a suitable ligand. Here we have prepared the diketone ligand having the amid group and its complex with Eu3+ ion. And we also examined the gelation of the complex. It was found out to form the gel from the complex in the mixture of chloroform and hexane. This gel formation is affected the chemical structure such as a length of the alkyl chain of the ligand. Details are under investigation.

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In recent years, self-propelled molecular assemblies in non-equilibrium system have drawn much attention in viewpoint of construction of inanimate chemical machinery. We have reported self-propelled oil droplets in a water-oil-surfactant emulsion (T. Toyota, et al, J. Am. Chem. Soc. 2009, 131, 5012-5013) As we found that oil droplets of heptyloxybenzaldehyde showed self-propelled motion in about 5 min in a solution of hexadecyltrimethylammonium bromide (50 mM), we tried to control the self-propelled motion of oil droplets which interact with each other for construction of high hierarchical non-linear dynamics of oil droplets. Regarding the surface electrostatic layer of oil droplets, we added nonanoic acid (150mM), in the emulsion of heptyloxybenzaldehyde (150 mM) and hexadecyltrimethylammonium bromide (50 mM) and found that oil droplets moved autonomously and some were grouped for 3-25 s and then parted from each other. It is to be noted that the oil droplets showed such cooperative dynamics in non-equilibrium system composed of simple lipophilic and amphiphilic compounds.

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Previously, we succeeded in stabilization of oligothiophene radical cations and steric control of intermolecular interaction by the use of annelation with bicyclo[2.2.2]octene. In this work, we synthesized oligothiophene which has thiol to be bonded with gold and bicyclooctene units to control intermolecular interaction. We have investigated SAMs on gold and gold-nanoparticles with those oligothiophenes and will report these results.

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Novel chiral metal-organic framework (MOF) has been synthesized using 2,2'-dihydroxy-1,1'-binaphthalene-6,6'-bis(4-benzoic acid) as chiral ligand. The enantiomer separation of some chiral sulfoxides by using the chiral MOF has also been studied.

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Cavitand has four modifiable sites on the aromatic rings. We designed and synthesized C_2V synmmetrical cavitand substituted benzamide groups as hydorogen bonding sites and pyridylethynyl groups as coordination bonding sites. The cavitand formed a hybrid supramolecular capsule in the presence of metal complex. The capsule could encapsulate sizable guest molecules accompanying structural alteration.

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Our research focuses on electron transfer coupled spin transition (ETCST) behavior, which has been observed in cobalt-iron cyanide-bridged complexes. We have already reported that the self-assembled cyanide-bridged decanuclear nickel-iron cage complex (Et₄N)[Ni(L^R)₂]₆[Fe(CN)₆]₄(PF₆) ( L^R = N-(2-pyridylmethylene)- (R)-1-phenylethylamine) has a spin ground state of S_T = 8. In this work, the magnetic properties of the self-assembled decanuclear cobalt-iron cage analogues (Et₄N)₂[Co(L^R)₂]₆[Fe(CN)₆]₄(X) ( X = BF₄^-(1), [Ni(mnt)₂]^-(2) (mnt = dimercaptomaleonitrile)), which were expected to show ETCST behavior, were investigated. The chi_mT value of 1 rapidly rose around 250 K as temperature increased, suggesting the occurrence of the ETCST phenomenon. On the other hand, 2 had a high-spin ground state at low temperature, resulting from ferromagnetic interactions between the cobalt-iron ions. This suggests that the magnetic properties of the cluster can be controlled through the choice of counter anion.

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Pyridyl and diethylenetriamino groups were introduced into thymidine. Reactions of the ligand and Pd complex gave new complexes. The structures of the complexes were determined by NMR and MS spectroscopy. In addition, the complex was compared with complexes that had the monodentate ligand instead of the diethylenetriamino groups.

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We have already reported the self-assembly of macrocyclic boronic esters by simply mixing diboronic acids and tetrol with indacene skeleton under equilibrating conditions. In the present study, we demonstrate the construction of two types of boronic esters containing ferrocene moieties by controlling the equilibration of boronic ester formation. While ferrocene dimer was generated under the equilibrating conditions, ferrocene trimer could be constructed by mixing the appropriate precursors in acetone, where the equilibration of boronic ester formation was suppressed.

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In order to form anion-driven 3D clusters, we have attempted to prepare radially arranged oligomers of dipyrrolyldiketone boron complexes as acyclic anion receptors. In fact, the trefoil-shaped trimers, which were obtained by Suzuki coupling, showed a variety of anion-driven assemblies such as helical assemblies and cage-like clusters, depending on the peripheral substituents and substituted positions of the 1,3,5-triphenylbenzene cores. The trimer shows higher anion-binding affinities, due to multiple binding sites. For receptor hexamers, which were obtained by cyclotrimerization reaction of ethynyl-bridged dimers, complicated conformations were observed in the absence of anions. Upon the addition of Cl–, NMR signals of pyrrole NH were shifted to downfield, suggesting the formations of [n+m]-type assemblies.

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A tris(phenylisoxazolyl)benzene self-assembles to form helical stacks. The introduction of a perylenebisimide unit onto the periphery of the tris(phenylisoxazolyl)benzene should give rise to a photo-functional assembly whose photochemical properties can be regulated by external stimuli. In this work, we investigated the self-assembling behavior and the photochemical property of chiral tris(phenylisoxazolyl)benzene 1 possessing a perylenebisimide unit. Its UV-vis and CD spectra changed in response to temperatures, suggesting that 1 stacked to form helical assemblies in solution.

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pai-conjugated molecules are attractive candidates for a wide variety of applications for optical and electronic materials because of its potential arise from inherent characteristic electronic states as well as its accumulated studies for the syntheses and exploration of properties. Especially, some pai-conjugated molecules are applied to soft materials by controlling of molecular orientation through supramolecular interaction such as pai-pai interaction and hydrogen-bonding. This time, we tried to synthesize a supramolecular polymer consist of benzoporphyrin derivative bearing cyanuric acid moieties and alkane derivative functionalized with complementary hydrogen-bonding site at both ends of molecular chain.

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We developed novel dynamic covalent polymers formed by intermolecular nucleophilic addition reactions among zwitterionic monomers. In particular, we designed and synthesized zwitterionic monomers which have both a trityl group as a relatively stable carbocation and a phenoxide as a highly nucleophilic anion. Through controlling the charges of the monomers by addition of acid or base, we examined the reversible formation of the polymers in detail.

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We have studied on the self-assemble behaviors of 1,3,5-triureabenzene derivatives carring amphiphilic side chains responsible to heat and pH of aqueous solution. This time, we designed and prepared the 1-aminoxyl-3,5-diureabenzene derivatives carring amphiphilic side chain. Those showed LCST (lower critical solution temperature) phenomena in water and formed ca.100 nm size self-assembly below LCST temperature, which were determined DLS (dynamic light scattering) and TEM (transmission electron microscopy) images. Above LCST temperature, their derivatives showed the turbidity in aqueous solution and formed some aggregated like globular particles. The magnetic property and the relaxivity for the radical derivatives will be also discussed.

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N-Phenylbenzohydroxamic acid showed solvent-dependent conformational change. We designed solvent-dependent fluorescence sensor moleucule by using hydroxamic acid structure as switching unit and two pyrene moieties as fluorophore. ¹H NMR spectra showed that the designed compound change the conformation solvent-dependently. It existed predominantly in trans form in DMF-d₇ or THF-d₈, while it existed in cis form in CDCl₃ or CD₂Cl₂. In the fluorescence spectra, it showed excimer fluorescence only in the solvent in which there was significant amount of cis conformers. Thus, the molecule showed solvent-dependent conformational alteration that caused change in the fluorescence properties. Since several types of aromatic amides can alter the conformation by change of some environmental conditions such as pH and Redox state, the present system would be applied to fluorescence sensor for various external stimuli.

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m-Calix[3]amide is a new family of cyclic oligomer, which is easily synthesized from alkylaminobenzoic acids by the self-condensation reaction, owing to the cis preference of N-alkylbenzanilide unit. m-Calix[3]amide is known to have two conformers in solution. The syn conformer has three benzene rings in the same orientation relative to the amide bond, and the anti conformer has one benzene ring turning in other direction. Because m-calix[3]amide preferentially adopts syn conformation, the appended substituents can be expected to have intimate interaction. We have already investigated the condensation reaction of 3-alkylaminobenzoic acid esters having oligothiophene at the 5-position and the optical properties of cyclic oligomers. We herein synthesized two m-calix[3]amides having pyrene as the chromophore at the meta-position and studied optical properties.

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Recently, we found that the benzannulation of o-(2-phenylethynyl)benzaldehyde with various alkynes was catalyzed by the rhenium complex to give the 2,3-disubstituted naphthalenes in moderate to good yields. Based on this finding, we applied this benzannulation protocol to the synthesis of highly elaborated helical molecules having 2,3-disubstituted naphthalene units.

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To prepare various saccharide−linked ethynylpyridine oligomers convergently, we developed synthetic routes in which a saccharide template was coupled with ethynylpyridine oligomers by Huisgen reaction in the final step. The higher−order structures of the oligomers were studied by UV-vis and CD spectroscopy in dichloromethane. The induced CD spectra revealed that the chirality of saccharide templates was transferred to the chirality of the helical structures of the oligomers.

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Recently, we successfully developed a synthetic method for long-chain o-phenylene oligomers and polymers, which are characterized by an elusive class of pi-conjugated architectures. We are now exploring physical and chemical properties of o-phenylenes, originating from a tight helical structure due to a steric requisite from the heavily angled aromatic connections. Here we report that the helical chirality of o-phenylene can be controlled when chiral secondary amides are incorporated into the termini of the molecule. Thus, the resulting o-phenylene derivatives exhibit strong CD signals. Interestingly, upon N-methylation of the amide groups, the CD sign is changed to give a CD spectrum, which is an approximately perfect mirror image to the original one. This observation indicates that the amide and its N-methylated functionalities give rise to an opposite stereochemical bias with one another, resulting in a helical inversion of the o-phenylene. We consider that the helical inversion is induced by a possible trans-cis conformational change of the terminal amide auxiliaries.

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Preferential enrichment is a symmetry-breaking chiral separation phenomenon that is initiated by the solvent-assisted solid-to-solid transformation of the first-formed metastable polymorphic form into a thermodynamically stable one during crystallization from the supersaturated solution of certain kinds of racemic mixed crystals (i.e., solid solutions or pseudoracemates) composed of two enantiomers in organic solvents without the aid of any external chiral element. Here, we report the classification of the crystal structures by using graph set analysis based on the hydrogen-bonding motifs. Using graph sets, we have observed interesting relationship between the occurrence of preferential enrichment and the crystal structures.

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Chiral aromatic alcohols are the key building block for many important pharmaceuticals and functional materials. We report that 2-menthoxybenzoic acid 1 is a versatile reagent not only for enantioresolution of aromatic alcohols, but also the determination of absolute configurations of the alcohols. For example, 1 was condensed with racemic cis-2, to yield diastereomeric esters. The diastereomeric esters were separated by reversed phase HPLC, and then the absolute configurations of the diastereomers were determined by the CD exciton chirality method.

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We previously reported that molecular crystal of p-tert-butylazacalix[5]arene pentamethyl ether forms a seemingly nonporous crystal, which adsorbs carbon dioxide selectively and rapidly under ambient conditions. To enhance gas adsorption property, we have newly designed its derivative in which tert-butyl groups are replaced by halogen atoms. Here we will report the synthesis, molecular and crystal structures, and gas adsorption behavior of chloriated azacalix[5]arene.

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A novel clathrand having a conformationally-rigid framework was synthesized by the Diels-Alder (DA) reaction of phencyclone with acenaphthylene and the inclusion property was investigated. The host DA adduct enclathrated ketones, cyclic ethers and aromatics. Especially, aromatic guests, such as benzene, were strongly incorporated within the host lattice, and the desolvation temperatures were extremely higher than the boiling point of the pure guests. The crystal structure of the clathrate indicated that weak lattice forces play important roles for host-host and host-guest recognitions, that is, the hosts are linked head-to-tail to form a "column" by the bidentate CH/O hydrogen bonds between phenanthrene ring hydrogens and bridged carbonyl oxygen as well as the pi/pi and CH/pi interactions between the stacking acenaphthene moieties. The aromatic guests are located in "space" between the host columns, in which edge-to-face (CH/pi) interactions between acenaphthene-ring hydrogens and benzene ring are operative. The inclusion behavior of the conformationally-rigid hosts of the same type are discussed on the basis of the thermal analysis, X-ray analysis and the semi-empirical MO calculation (PM6) data.

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Polymorphism plays an important role in the physical properties of organic crystals and thus the selective growth of a desired polymorph of a given compound is very important. We have recently discovered that a new polymorph selectively grows on the (010) surface of an organic single crystal substrate by exposure to 2-picoline vapor. Global real-space analysis of crystal epitaxy (GRACE) program has suggested that this interesting selective growth of the new polymorph results from the epitaxial relationship between the (010) surface of the substrate and the new polymorph. The detail of the results will be discussed.

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Previously, we found that the macrocycle having bisamide component can bind phenanthroline derivatives very strongly, yielding the neutral pseudorotaxane. This inclusion complexes show a pH controllable reversible threading-dethreading molecular switching system. Here, we report the pseudorotaxane structure obtained from single crystal by X-ray crystallography and synthesis of the neutral rotaxane, whose structure we confirmed by NOESY spectra.

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Rotaxane comprised of Cs-symmetric wheel component and unsymmetrical axle component generates planar chirality. The asymmetric field is strongly dependent on the unique dynamic behavior of the rotaxane such as shuttling. In this work, we synthesized poly(m-diethynylbenzene) bearing optically active planar chiral rotaxane on the side chain, and the helical structure of the polymer was studied.

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This study features the synthesis and characterization of rotaxanes consisting of alpha,omega-diaminoalkane as an axle, cyclodextrin or derivatives as a wheel, and bulky isocyanate as an end-capping agent. The scope and limitation concerning the formation of the inclusion complex were investigated mainly to find the direction and number of cyclodextrin of the rotaxane.

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The structure of lithium phenolates have been studied extensively and it is known that they exist as various aggregation states. However, the hexameric lithium phenolate (ArOLi)₆ bearing hexagonal-prismatic Li₆O₆ core is too unstable to exist at room temperature probably due to the steric hindrance between their aromatic rings. We have developed the method to control Lewis acidity of the group 13 metal complexes by using the cage-shaped ligands bearing three phenoxy moieties. These aryloxy tridentate ligands limit the mobility of the ligand and thus lead to the facile isolation and structural characterization of a number of metal complexes that have been difficult to form by using aryloxy monodentate ligands. In this study, we synthesized stable hexametallic lithium phenolates bearing hexagonal-prismatic Li₆O₆ core by using cage-shaped tridentate ligands. Their solid structures were analyzed by X-ray crystallography. NMR study revealed their behavior in solution and they existed as a hexametallic structure at room temperature.

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N-Phenylmonoaza-15-crown-5 ether and their derivatives was synthesized and served for ion selective PVC membrane electrode. Nernst response of electrode to Fe²⁺/Fe³⁺ under various conditions, as well as the structure and stability constants of host-Fe²⁺/Fe³⁺ complexes in acetonitrile solution were investigated. The mechanism of Fe²⁺/Fe³⁺ selectivity of membrane electrode will be discussed.

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Photochromic compounds, which show reversible switching between two isomers having different optical properties by photoirradiation, have attracted much attention because of the potential application to optical memory devices, molecular machines, and switchable molecular receptors. Azobenzene is one of the most commonly used photochromic compounds, which features a light-induced trans-cis isomerization. Photoisomerization of azobenzene results in a drastically structural change, followed by the change of properties and functions. Macrocyclic compounds bearing an azobenzene moiety are especially attracted with respect to switching of various functions because structural change based on photochromism can affect the structure and function of macromolecule. In this work, azobenzene-linked chelate ligands were prepared and photoresponsive macrocyclic compounds were constructed by complexation of the ligands.

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We synthesized the photo-driven host molecule with a stiff-stilbene as a photo-driven moiety and a cavitand as a guest recognition moiety, and studied the inclusion phenomena wuth C60 as guest. But this host molecule did not show strong binding with C60. Therefore, we planned to use Calix[5]resorcinarene moiety as an alternative guest recognition moiety and studied the synthesis of this new system, whose inclusion phenomena and photo-switching properties will be reported.

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We have been developed imidazolium-based anion receptors using both of electrostatic and CH-anion hydrogen bonding interactions. Recently, we found pentakis(aryl-substituted) imidazolium forms an anion-pi interaction type complex with fluoride in the solution state. Now, we will report the complexation between 1,3,4,5-tetraarylimidazolium and fluoride ions. Although the cation has a C-H proton can form hydrogen bonding with anion, the tetraarylimidazolium cation exists predominately the anion-pi interaction type complex.

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Recently, much attention has been paid to the functionalization at the 1,8-positions of carbazole in order to explore novel carbazole-based functional materials. We designed and synthesized carbazole derivatives incorporated with anthracene or pyrene units at 1,8-positions, and found that they could serve as molecular receptors for p-acceptors on the basis of NMR and UV/Vis spectroscopic methods.

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Macrocyclic host molecules which consist of pyridine rings linked with acetylene bonds were developed. Their preparation was carried out by Sonogashira reaction and oxidative coupling reaction of alkynes. Pyridone or inversed pyridine rings were introduced on the precursor for the cyclization reaction to stabilize cisoid conformation. The resulting macrocyclic molecules recognize saccharide guests and show induced CDs.

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Cryptand-like porphyrinoids composed of three arms of 1,3-bis(2-pyrryl)arenes are regarded as having great potential in the host-guest chemistry, but their tripyrrylmethane connection node is easily oxidized to lead to degradation especially under acidic conditions in the light. We intended to replace the bridgehead hydrogens by inert groups with the objective of improving stability against air-oxidation. In this work, we have found that cyclotetrapyrrolebispyridine underwent nucleophilic addition of cyanide at both meso-like positions. DDQ oxidation followed by the reaction with 1,3-bis(2-pyrryl)benzene proceeded under acidic conditions to give the target cryptand. The splitting pattern in the ¹H NMR spectrum of this cyptand indicates C₂ molecular symmetry, which means helicity inversion is inhibited by the introduction of cyano groups at the bridgehead. We will report on how far it has been stabilize and what is its binding property.

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We synthesized mono-deprotected pillar[5]arene by controlling the deprotection reaction. From the mono-functionalized pillar[5]arene, various supramolecular architectures such as a self-inclusion complex and pillar[5]arene dimer were constructed.

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This study features successive reaction with palladium-templated macrocyclic catalyst. When a linear molecule having allylurethane was treated with the Pd-containing macrocycle, the successive cyclization reactions were achieved as a result of the translation of the macrocycle along the linear molecule by taking pseudorotaxane structure. The broad scope and limitation of the catalytic reaction were also examined.

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Sonogashira-Hagihara cross-coupling reaction in a stepwise fashion enabled to synthesize precursors of paraphenyleneacetylene macrocycles in better yield than a one-pot fashion. This stepwise synthesis allowed to elaborate cyclophanes containing one metaphenylene or orthophenylene. When we carried out reductive aromatization reactions of cyclophanes with a tin-reagent and a fullerene, we observed the formation of pi-conjugated cyclynes as an inclusion complex with a fullerene.

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The design and synthesis of nanotubes on pure covalent bonds is still a challenge for organic chemists. For the construction of cyclophane-based structural units, we have chosen pyromellitic diimide moiety. Pyromellitic diimide is a pai-electron acceptor, thus the selective incluison of an electron-rich guest is expected via a charge transfer interaction. Synthesis of artificial nanotubes can be done by connecting suitable spacer molecules with the functionalized pyromellitic diimide-based cyclophanes, followed by connecting the resultant capsule with another cyclophanes. We have synthesized the diimide-based cyclophanes by the dehydration between an amine and an anhydride and studied the inclusion properties of electron-rich guest molecules in the cavity. We would like to extend these cyclopahnes for symthesis of artificaial molecular tubes and study the inclusion of electron-rich guest molecules in the empty cyclindrical cavity.

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To develop a new two-photon luminescence material a large cyclic tetramer composed of carbazole was synthesized by connecting with ethynyl groups. Because the pi conjugate system expanded by the acetylene bridge and the pi electron would be delocalized, appearance of a new optical function is expected. Moreover, large cyclic pi conjugate systems were constructed with the formation of the cyclic tetramer that closed the connected body of the carbazole, and the red shifts of the fluorescent wave length by expanding the pi conjugation system were suggested.

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The development of novel acene structures is of great interest due to their potential applications for organic electronics like field-effect transistors. In this regard, we have newly designed and synthesized three thiophene-fused anthracene derivatives, dithieno[a,c]anthracenes. Our synthetic methodology is based on successive the aryl-aryl coupling and Bergman cyclization in a one-pot procedure. It is well known that the reactivity of cyclic enediynes in Bergman cyclization are deeply depends on the distance of acethylene carbon atoms of the enediyne systems. In this presentation, we will report on the synthesis and structure-property relationship of new thiopene-fused acene derivatives.

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Acenes that are larger than anthracene have been attractive and used as organic semiconductors. On the other hand, the smaller acenes such as naphthalene have been relatively unexplored. Herein, we report concise synthesis of [n]cyclo-2,7-naphthylenes ([n]CNAP), and their performance as bipolar carrier transport materials in organic light-emitting diode (OLED) devices.
A series of [n]CNAP was synthesized by a nickel promoted coupling reaction of 2,7-dibromonaphthalene, and three major congeners (n = 5, 6, and 7) were isolated in 1, 24, and 12% yield, respectively. The reaction was readily scalable and isolation of abundant [6]-, and [7]CNAP was successfully achieved without recourse to chromatographic methods, which allowed the gram-scale preparation of [6]CNAP. The structures of all the isolated CNAP were established by single-crystal X-ray analysis. Thermogravimetric analysis showed the highly resistant characters of CNAP. The carrier transport performance of [6]- and [7]CNAP was evaluated in phosphorescent OLED devices. The performance as a hole and electron transport ability was comparable or higher than that of standard materials, a-NPD and Alq₃.

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Cycloparaphenylenes (CPPs) are the cyclic oligoarenes composed of solely para-substituted benzenes. For nearly one century, CPPs have attracted significant attention of scientists because of their simple and beautiful structure. Despite extensive trials of synthetic chemists, however, it was only very recently that some CPPs have finally been synthesized by the groups of Bertozzi, Itami, and Yamago. More recently, we have reported a new strategy using the cyclohexane-inserted U- shaped units for the modular and size-selective synthesis of [n]CPPs (demonstrated for n = 14–16). We herein report the synthesis of nitrogen-containing carbon nanorings. We expect that two 2,2'- bipyridine or 2,2'-bipyrimidine units, inserted into the CPP structure, have an ability of ligation to metal center to form supramolecular nanotubes.

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Phenanthrene-fused dehydro[12]- and [18]annulenes were prepared and their respective antiaromaticity and aromaticity were revealed by various spectroscopic measurements and theoretical calculations.

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We have synthesized trigonally-expanded tetrakisdehydrobenzo[12]annulene (TDBA) derivatives which comprise radially-connected three dehydrobenzo[12]annulene (DBA) units on the central DBA core via Mo-catalyzed alkyne metathesis reaction. tert-Butyl substituted TDBA showed a large two-photon absorption cross section among hydrocarbons. In addition, TDBA having branched alkyl ester groups displayed a columnar liquid crystalline phase.

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Recently, investigation on the construction the two-dimensional (2D) porous molecular networks on surface with few-nanometer periodicity based on self-assembly of organic molecules has been paid great attention due to their use in the construction of multicomponent molecular ordering via the guest co-adsorption or selective deposition of metal ions at the pores. Our scanning tunneling microscopy (STM) observation revealed that dehydrobenzo[12]annulene (DBA) substituted with six long alkoxy chains bearing perfluoroalkyl groups at the end of the three alkoxy chains formed a 2D porous honeycomb network at the liquid/solid interface, where the fluorinated alkyl groups were placed around the pore. We have been investigating the possibility of selective co-adsorption of guest molecules at the fluorinated pore via fluorophilic interaction.

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A pi-conjugated cyclic molecule, octadehydrodibenzo[12]annulene, is expected to experience topochemical polymerization, which yields ladder-shaped ene-yne conjugated polymers. In this study, to control a way of pi-stacking of the annulene cores, a phenyl-substituted annulene derivative at the ortho-position was synthesized. The derivative construct columnar pi-stacked superstructures, which are geometrically suitable for topochemical polymerization.

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The reaction of cyclopentadiene condensed with 1,6-methano[10]annulene at 2,3-positions with dichloroketene gave cycloadduct. The hydrolysis of the adduct gave two isomer of 1,6-methano-2,3-tropolono[10]annulene (1) and (2). Then 1,6-methano-3,4-cyclopentadieno[10]annulene was prepared from 3,4-diformylfuran, and then the synthesis of 1,6-methano-3,4-tropono[10]annulene is now under investigation.

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We have synthesized acetylene extended radiaannulenes having dicyanomethylene groups at exo positions (1 and 2), and determined the structure of 1 by X-ray crystallographic analysis. CV measurement revealed the strong electron coupling of two redox groups of 1. We will report the detail of them together with their electronic spectra.

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