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[Ru(bpy) 2 (bqdiBr 2 )](PF 6 ) 2 ([ 1 ](PF 6 ) 2 , bpy = 2,2′-bipyridyl, bqdiBr 2 = 3,6-dibromo-1,2-benzoquinone diimine) was synthesized by the reaction of 3,6-dibromo-1,2-phenylenediamine with [RuCl 2 (bpy) 2 ] in air, and the reactivity of [ 1 ](PF 6 ) 2 in Pd-catalyzed cross-coupling reactions with metalated thiophene and benzene was investigated. The structure of [ 1 ](PF 6 ) 2 was determined using X-ray crystallography. The Migita–Kosugi–Stille cross-coupling of [ 1 ](PF 6 ) 2 with 2 equiv of Th-SnBu 3 (Th = 2-thienyl; Bu = butyl) afforded a 3,6-di(2-thienyl)-1,2-benzoquinone diimine (Th-C 6 H 2 (NH) 2 -Th)-coordinated Ru(II) complex [ 2 ](PF 6 ) 2 . Similarly, the Suzuki–Miyaura cross-coupling of [ 1 ](PF 6 ) 2 with 2 equiv of CH 3 OC 6 H 4 -B(OH) 2 - p proceeded smoothly to afford a p -CH 3 OC 6 H 4 -C 6 H 2 (NH) 2 -C 6 H 4 OCH 3 - p -coodinated Ru(II) complex, [ 3 ](PF 6 ) 2 . The optical and electrochemical properties of these complexes were evaluated based on the presence of the extended π-conjugated diimine ligand in the diimine moiety. The Stille cross-coupling of [ 1 ](PF 6 ) 2 with 1 equiv of Me 3 Sn-C 4 H 2 S-SnMe 3 (C 4 H 2 S: thiophene-2,5-diyl) afforded a π-conjugated polymer consisting of the [Ru(bpy) 2 (bqdi)] 2+ units.

Homocoupling of aryl halides (2 ArX → Ar―Ar) promoted by NiCl2/2,2′-bipyridine (bpy)/Mg mixtures in DMF has been studied. Mixtures of NiCl2, bpy and Mg in DMF promoted homocoupling of aryl halides such as phenyl bromide and p-tolyl bromide to give the coupling products in good (e.g. approximately 60–75%) yields, and the homocoupling products were easily isolated from the reaction mixtures. Application of this homocoupling to dibromo-aromatic compounds (Br–arylene–Br: 2,5-dibromopyridine, 2,7-dibromo-9.9-dioctylfluorene and 2,7-dibromo-9,10-dioctyl-9,10-dihydrophenanthrene) gave the corresponding π-conjugated polymers, –(arylene)n–, in good yields. Organometallic processes for the homocoupling are discussed. Copyright © 2014 John Wiley & Sons, Ltd.

New polymer electrolytes consisting of diphenyl sulfone units with –O–(CH2)3SO3M (M = H or Na) side chains have been prepared. Dehalogenative polycondensation using a zero-valent nickel complex, [Ni(0)Lm], gave a homopolymer, Polymer-1(Na), from Cl–Ph(R)–SO2–Ph(R)–Cl (monomer-1; Ph(R) = 1,3-phenylene unit having the –O–(CH2)3SO3Na side group at the 4-position). Protonolysis of Polymer-1(Na) gave Polymer-1(H) with a weight average molecular weight of 25,000. Polymer-2(H) was synthesized by Suzuki-Miyaura cross coupling of Br–Ph(R)–SO2–Ph(R)–Br (monomer-2) and C6H4(B(OH)2)2-p using [Pd(PPh3)4] and ensuing protonolysis. Crosslinking of Polymer-2(H) with 1,4-benzenedimethanol gave a water-protected film. The cross-linked film of Polymer-2(H) showed proton conductivity of 0.26 S cm−1 at 80 °C and 90% humidity.

π-Conjugated polymers consisting of 1,10-phenanthroline units and crown ether subunits (Poly-1, Poly-2, and Poly-3) were prepared by dehalogenation polycondensation of the corresponding dibromo monomers using a zero-valent nickel complex as a condensing agent. They were characterized by elemental analysis, 1H NMR and UV–Vis spectroscopies, and cyclic voltammetry (CV). They were partly soluble in CHCl3, and the number average molecular weight of the soluble part of Poly-2, which had 15-crown-5 subunits, was estimated to be 5300. The polymers exhibited UV–Vis peaks at approximately λmax = 360 nm, which was reasonable. Complexation with [Ru(bpy)2]2+ and alkaline metal ions made the polymer soluble in organic solvents. The complexation of [Ru(bpy)2]2+ to the 1,10-phenanthroline unit proceeded quantitatively, and the [Ru(bpy)2]2+ complexes exhibited CV curves characteristic of [Ru(N-N)3]2+ complexes.

π-Conjugated polymers based on indigo unit were prepared. Dehalogenative polycondensation of N-hexyl-6,6'-dibromoindigo with a zerovalent nickel complex gave a homopolymer, P(HexI), in 77% yield. Copolymer of N-hexyl-indigo and pyridine, P(HexI-Py), was also prepared in 50% yield. P(HexI) showed good solubility in organic solvents, whereas P(HexI-Py) was only soluble in acids such as HCOOH. The weight-average molecular weights (Mw) of P(HexI) and P(HexI-Py) were determined to be 10,000 and 40,000, respectively, by a light scattering method. Pd-catalyzed polycondensation between 6,6'-dibromoindigo with N-BOC (BOC = t-butoxycarbonyl) substituents and a diboronic compound of 9,9-dioctylfluorene afforded the corresponding alternating copolymer, P(BOCI-Flu), as a deep red solid in 98% yield. P(BOCI-Flu) was soluble in N-methyl-2-pyrroridone and showed an Mw of 29,000 in GPC analysis. Treatment of P(BOCI-Flu) with CF3COOH smoothly led to a BOC-deprotection reaction to give an insoluble deep green polymer, P(I-Flu), in a quantitative yield. Diffuse reflectance spectra of powdery P(BOCI-Flu) and P(I-Flu) showed peaks at about 580 nm and 630 nm, respectively, which are thought to originate from the indigo unit.

Preparation of proton conducting PVA-PSS polymer films composed of cross-linked poly(vinyl alcohol) (PVA) and poly(styrene sulfonic acid) (PSS) is described. The PVA-PSS film was insolubilized in hot water by the crosslinking reaction with succinic acid (SA) in a temperature range of 180–200 °C. Insolubilization of the PVA-PSS film in hot water was also achieved by self-crosslinking that occurred in the PVA-PSS system in a temperature range of 130–180 °C, even in the absence of SA. This self-crosslinking in the PVA-PSS system is thought to proceed via PSS-catalyzed dehydration of PVA to form olefinic CH CH − units and ethereal O − units. Coloring of the PVA-PSS film to black by thermal treatment supported the formation of π-conjugated (CH CH) n − units. Both the PVA-PSS-SA and PVA-PSS films showed proton conductivity of approximately σ = 0.1 S cm − 1 at 80 °C and 95% relative humidity. The self-crosslinking observed with the PVA-PSS system was followed by gravimetry.

Two new cross π-conjugated polyketones, (Ar CO Ar C 6 H 2 (OC 12 H 25 ) 2 ) n (Ar = p -phenylene ( Polymer-1 ) and pyridine-2,5-diyl ( Polymer-2 )) have been synthesized via Suzuki-type organometallic polycondensation. Polymer-1 and Polymer-2 had number average molecular weights ( M n ) of 32,000 and 8000, respectively, in GPC analysis and were thermally stable up to 300 °C under N 2 . Polymer-1 and Polymer-2 showed photoluminescence (PL) peaks at λ EM = 466 and 515 nm in chloroform with quantum yields of Φ = 0.46 and 0.04, respectively. The PL peak position of Polymer-1 agrees with the electroluminescence (EL) peak observed with an ITO/PEDOT-PSS/ Polymer-1 /Ba:Al PLED configuration ( λ EL = 460 nm). PLs of Polymer-1 and Polymer-2 showed phosphorescence characteristics with long decay lifetimes of 0.58 and 1.08 s and quantum yields of 20% and 19% at 77 K in frozen glass matrices, respectively. Cyclic voltammograms of Polymer-1 and Polymer-2 films on a Pt plate showed electrochemical reduction (n-doping) peaks at −2.17 and −1.91 V vs. Ag + /Ag, respectively.

The reaction of 2,5-diiodo-1,4-benzenedicarbonyl chloride, C6H2I2(COCl)2-p, with 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO-ol) gave I–Ph(COO–TEMPO)2–I, Monomer-1. Pd-catalyzed polycondensation of Monomer-1 with Me3Sn-Th-SnMe3 (2,5-bis(trimethylstannyl)thiophene) and Bu3Sn–CH = CH–SnBu3 (1,2-bis-(tributylstannyl)ethylene) gave the corresponding π-conjugated polymers, Polymer-1 and Polymer-2, respectively. Monomer-1 was converted to a diethynyl compound, H–C ≡ C–Ph(COO–TEMPO)2–C ≡ C–H (Monomer-1'), and Pd-catalyzed polycondensation between Monomer-1 and Monomer-1' gave a π-conjugated poly(arylene ethynylene) type polymer, Polymer-3. According to the expansion of the π-conjugation system by the polymerization, the UV–vis peaks of Monomer-1 (λmax = 323 nm) and Monomer-1' (327 nm) are shifted to longer wavelengths (λmax = 365 nm, 385 nm, and 396 nm for Polymer-1, Polymer-2, and Polymer-3, respectively). Polymer-1–Polymer-3 showed ESR signals at about g = 2.01 with reasonable intensities. They are electrochemically active and showed a peak current anodic (oxidation) peak at about 0.9 V versus Ag/AgCl, which is reasonable for TEMPO polymers. Copyright © 2013 John Wiley & Sons, Ltd.

π-Conjugated polymers based on 1-aminopyrrole and 4-amino-1,2,4-triazole were prepared. Pd-catalyzed organometallic polycondensation gave poly(arylene-ethynylene) (PAE)-type π-conjugated polymers consisting of BOC-protected 4-amino-1,2,4-triazole ( Taz(BOC) ) units (BOC = t -butoxycarbonyl). The number average molecular weights ( M n ) were determined to be 5200–19,200 using GPC. An alternating copolymer of Taz(BOC) and bithiophene (Th–Th) units, P(Taz(BOC)-Th-Th) n -Pd , with an M n of 10,800 was also prepared by Pd-catalyzed organometallic polycondensation. (Taz(BOC)-Th-Th) n -Pd showed a UV–Vis absorption peak at λ max = 425 nm, which is reasonable for a π-conjugated five-membered ring polymer with a coplanar structure. The deprotection of the BOC group of the polymers proceeded at 200 °C; this BOC-deprotection was investigated using a model compound. The optical and electrochemical properties of the π-conjugated polymers are reported.

Electrochemical oxidative copolymerization was carried out between pyrrole and N-substituted pyrroles, Pr(C C Ph) (Ph = phenyl) and Pr(C C SiEt3), which have C C Ph and C C SiEt3 groups, respectively, at the N-position of pyrrole. The electrochemical oxidation of Pr(C C Ph) and Pr(C C SiEt3) required potentials about 0.5–0.8 V higher than that of pyrrole because of the presence of the electron-pulling acetylenic group, and the electrochemical copolymerization gave copolymers with pyrrole-rich compositions. Copolymers of pyrrole with Pr(C C Ph) showed an electrical conductivity of 2–6.3 S cm−1. These copolymers showed thermal stability: 50–85 °C higher than the homopolymer of pyrrole. A dimeric compound of Pr(C C Ph), i.e., (Pr C C Ph)2, was prepared, and its X-ray crystallographic analysis essentially revealed a pyrrole–pyrrole coplanar structure; this supports the notion that the C C Ph group attached at the N-position of pyrrole does not break π-conjugation in the polypyrrole main chain of the copolymer.

Poly(2-pyridone-3,5-diyl)s with –(CH 2 ) 4 –SO 3 M (M = H or Na) side chains have been prepared by nickel-complex promoted dehalogenative polycondensation. A composite film of the polymer with –(CH 2 ) 4 –SO 3 H side chains and poly(vinyl alcohol) showed a proton conductivity of 1.5 × 10 −1 S cm −1 at 80 °C and 95% humidity. A copolymer with pyridine showed a high stability against oxidation by a Fenton reagent.

Chemical oxidative polymerization (COP) of 3-hexylthiophene in polar solvents, such as CH3CN and CH2Cl2, smoothly proceeded at temperatures below 0 °C to afford regio-controlled poly(3-hexylthiophene-2,5-diyl) (P3HexTh) with a head-to-tail (HT) content of higher than 80%. Use of CH3CN at −40 °C gave P3HexTh with 83% HT content, Mn (number-average molecular weight) of 42 000, and a relatively narrow polydispersity of 1.6. Obtained P3HexTh formed an ordered structure in solid, and NOBF4-treated film of P3HexTh with the HT content of 83% showed electrical conductivity of 3.0 S cm−1.

Dibromopyridines or dibromopyridone with –(CH2)m–SO3Na group(s) has been prepared via the reactions of the corresponding dibromopyridines with –OH and –NH2 groups with sultone. These compounds were converted into polymers with the –(CH2)m–SO3H groups via organometallic polycondensation. The polymer showed proton conducting properties and high stability toward oxidation.

We have investigated the structural and electrical characteristics of two kinds of block co-oligomers, 5,5″-Bis(2-pyridyl)-2,2′:5′,2″-terthiophene (5A) and 2,5-Bis(2-(2′-thienyl)-pyridine-5-yl)thiophene (5B), which are composed of electron-donating thiophene and electron-withdrawing pyridine rings. At the view of building block units, the amount of the module units included in these molecules is completely equivalent to each other. X-ray diffraction patterns of 5A and 5B thin films grown on atomically flat α -Al 2 O 3 (0001) substrates indicated a high degree of orientation along the c- axis. Field-effect transistors (FETs) of 5A and 5B thin films were fabricated and evaluated without exposure to air. The FETs based on 5A active layers exhibited p -type behavior with a mobility of ~ 10 −3 cm 2 /V·s and an on–off ratio of 10 4 , while no switching behavior was observed in FETs based on 5B active layers. The lower highest occupied molecular orbital (HOMO) of 5B than that of 5A in the quantum-chemical calculation might explain these FET behaviors. Thus, HOMO, lowest unoccupied molecular orbital (LUMO) levels and FET actions of the co-oligomer molecules that consist of the same amount of building blocks can be controlled by the sequence of electron-donating and electron-withdrawing building blocks.

π-Conjugated polymers consisting of 9,10-disubstituted 9,10-dihydrophenenthrene, with the substituents octyl, 2-ethylhexyl, -OSiBu3, etc., units are prepared by organometallic polycondensation. Homopolymers (PH2Ph(9,10-R)) have a π-conjugation system similar to that of polymers of 9,9-dialkylfluorene and show UV-Vis peaks at ≈380 nm. In addition to the peak at ≈380 nm, some homopolymers give rise to a peak at a longer wavelength, suggesting molecular assembly of the polymers. X-ray diffraction data support the molecular assembly. The homopolymers show photoluminescence (PL) with PL peaks at ≈430 nm, and PL spectrum of the polymer film is essentially unchanged after heating the polymer film at 150 °C in air. The homopolymers undergo electrochemical p-doping at about 1.5 V versus Ag+/Ag.

Alternating π-conjugated copolymers of 1,8-naphthyridine-2,6-diyl (1,8-Nap) with 9,9-dioctylfluorene-2,7-diyl (P(Flu-Ph-1,8-Nap)) and 2,5-didodecyloxy-1,4-phenylene (P(ROPh-Ph-1,8-Nap)) have been synthesized by Pd-catalyzed organometallic polycondensation. The copolymers showed UV-vis absorption peaks at around 390 nm in o-dichlorobenzene. The polymers were photoluminescent both in o-dichlorobenzene and in the solid state. In o-dichlorobenzene, the emission peaks of P(Flu-Ph-1,8-Nap) and P(ROPh-Ph-1.,8-Nap) appeared at λEM = 440 and 471 nm, with quantum yields of 87% and 66%, respectively. Electrochemical data revealed that 1,8-Nap behaved as a typical electron-accepting unit. When P(Flu-Ph-1,8-Nap) was treated with 10-camphorsulfonic acid, the emission peak shifted to λEM = 598 nm. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011

π-Conjugated poly(aryleneethynylene)s consisting of N,N′-bis(salicylidene)-1,2-phenylenediamine (salophen) units (Poly-1−Poly-3) and salophen−nickel complex units (Poly-1−Ni) were prepared in high yields by the palladium-catalyzed polycondensation of H−≡−Ar−≡−H (Ar = fluorene or 2,5-dialkoxy-p-phenylene) with dibromo compounds of salophen (Br2−Salophen) and its nickel complex (Br2−Salophen−Ni), respectively. The Ni-free polymers (Poly-1−Poly-3) showed good solubility in CHCl3 and THF, had high thermal stability, and exhibited number-average molecular weights (Mn) of 9200−14000 in GPC analysis. The UV−vis spectra of the polymers showed π−π* transition peaks at about 420 nm, which was comparable to those of poly(p-phenyleneethynylene)s. The UV−vis spectrum of Poly-1−Ni exhibited additional intermediate and small peaks at about 480 and 600 nm, which were assigned to a charge-transfer (CT) electronic transition and a d−d transition, respectively. The complexation of Poly-1 with Ni2+ proceeded clearly and quan...

We propose a new approach to nanoscience and technology for ionic liquids (ILs): molecular beam deposition of IL in ultrahigh vacuum by using a continuous wave infrared (CW-IR) laser deposition technique. This approach has made it possible to prepare a variety of "nano-IL" with the given composition on the substrate: a nanodroplet, on one hand, the volume of which goes down to 1 aL and, on the other hand, an ultrathin film with a thickness to several 100 nm or less. The result of fractional distillation of a binary mixture of ILs, investigated by nuclear magnetic resonance as well as electrospray ionization time-of-flight mass spectrometry, indicates that this deposition process is based on the thermal evaporation of ILs, and thus this process also can be used as a new purification method of ILs in vacuum. Furthermore, the fabrication of binary mixture droplets of two ILs on the substrate by alternating deposition of two ILs was demonstrated; the homogeneity of the composition was confirmed even for one single droplet by high-spatial-resolution Raman spectroscopy.

A series of π-conjugated alternating copolymers consisting of Th-ITN-Th and p-C 6 H 2 (OR) 2 units were synthesized. XRD indicated that the copolymers assume an interdigitation packing mode, and UV-Vis spectra revealed a strong tendency for self-assembly. Upon molecular assembly of the copolymer, the UV-Vis absorption shifted by about 100 nm to a longer wavelength from that of the single molecule. The copolymers underwent electrochemical oxidation (or p-doping) and reduction (or n-doping) at 0.2 and -2.0 V versus Ag + /Ag, respectively. A p-doped copolymer film showed an electrical conductivity of 182 S · cm -1 , and the temperature dependence of electrical conductivity was measured. The copolymer showed piezochromism and served as a p-channel material for a field-effect transistor.

Organometallic polycondensations give various π-conjugated polymers. For example, nickel complex-promoted dehalogenative polycondensation of dihaloaromatic compounds and dihalogenataed heterocyles,...

Reactions of N-(2,4-dinitrophenyl)-4-arylpyridinium chlorides (aryl (Ar) = phenyl and 4-pyridyl) with piperazines caused the ring opening of the pyridinium ring and yielded polymers that consisted of 5-piperazinium-3-aryl-penta-2,4-dienylideneammonium chloride units [ N(CH(R)CH2)2N+(Cl−) CH CH C(Ar) CH CH , R H, Me, and phenyl]. However, the same reactions occurring in the presence of piperidine yielded oligomers that consisted of 5-piperazinium-3-aryl-penta-2,4-dienylideneammonium chloride units having piperidine and/or piperazine rings at both ends. 1H NMR spectra suggested that π-electrons of the penta-2,4-dienylideneammonium group of the polymers and the oligomers were delocalized. UV–vis measurements revealed that the π-conjugation system expanded along the polymer and oligomer chains due to the orbital interaction between electrons on the two nitrogen atoms of the piperazinium ring. Conversion of the piperazinium ring from the boat form to the chair form caused decrease in the π-conjugation length. The rate constants of the conversion of the oligomers depended on their chain lengths. The surface of pellets that were molded from the polymers and oligomers exhibited metallic luster. These polymers and oligomers underwent electrochemical oxidation in solution.

Nickel(II) complexes bearing a κ3SNS pincer ligand, 2,5-bis(benzylaminothiocarbonyl)pyrrolyl (L1) and a κ3SCS-pincer ligand, 2,6-bis(benzylaminothiocarbonyl)phenyl (L2), were synthesized, and their structures and electrochemical properties were elucidated. The crystal structures of [Ni(SNS)Br] (2) and [Ni(SCS)Br] (5) were determined by X-ray crystallography. The electrochemical and crystallographic data obtained from the complexes revealed that the κ3SCS ligand has a stronger electron-donating ability than the κ3SNS ligand.

π-Conjugated polymers are used in many industrial applications and are expected to become an integral part of future electronic and optical technologies. Molecular self-assembly is a promising method for improving the functionality and utility of π-conjugated polymers. The carrier mobility in polymer materials produced by self-assembly is influenced by the morphology and state of molecular assembly in a similar manner to the influence of crystallinity and amorphism in silicon. π-Conjugated polythiophenes with controlled molecular structures and long side chains often form π-stacked structures by self-assembly through side-chain aggregation. Such polythiophenes have higher carrier mobility, optical third-order nonlinear susceptibility and Verdet constant compared with π-conjugated polythiophenes that do not self-assemble. This review covers the development and functionalities of self-assembled π-conjugated polythiophenes with regio-regular head-to-tail, Th(R)–Ar–Th(R) and head-to-head structures with alkynyl side chains.

A series of poly(diphenylamine)s with substituents at the N-position, (C 6 H 4 ―p―NR-C 6 H 4 ―p) n (R = methyl, butyl, hexyl, and benzoyl), were prepared by organometallic polycondensation using a zerovalent nickel complex. These polymers were soluble in organic solvents such as THF, N-methylpyrrolidone (NMP), and trifluoroacetic acid (TFA), and gave intrinsic viscosity of 0.52―0.93 dL g ―1 . They showed number average molecular weights (M n ) of 3400―6100 with M w /M n (M w = weight average molecular weight) of 1.9―2.4 in GPC analysis. The polymers exhibited photoluminescence (PL) with emission peaks at λ EM = 408―425 nm in NMP solutions.

Self-assembly of polythiophenes with –C≡CR (R = alkyl, phenyl, etc.) side chains has been investigated. Seven new polymers consisting of head-to-head and tail-to-tail 2,2′-bithiophenes with –C≡CR s...

New π-conjugated pyrimidopyrimidine polymers with two different alkylamino groups at C4 and C8 positions, PPympym(4-NH-n-C 8 H 17 -8-NHR) (R=n-C 4 H 9 , n-C 6 H 13 , n-C 12 H 25 , and n-C 16 H 33 ), were prepared by dehalogenation polycondensation using nickel zerovalent complex in high yield. The obtained polymers were partly soluble in organic solvents such as chloroform. A chloroform soluble part of PPympym(4-NH-n-C 8 H 17 -8-NH-n-C 16 H 33 ) showed a number-average molecular weight of about 3,000 in GPC analysis. UV-vis spectra of the polymers in CHCl 3 showed a π-π* absorption peak at about 450 nm, and the peak position shifted by 30 nm to a longer wavelength in film. The polymers showed photoluminescence both in solution and in film. Cast films of the polymers were electrochemically reduced at about -2.3 V vs. Ag + /Ag. XRD patterns of the polymers revealed the polymers took an end-to-end packed structure.

The photochemical properties of pincer platinum complexes bearing secondary thioamide groups have been examined. The presence of the coordinated secondary thioamide linkage in the pincer ligand was found to work as a reactive site upon addition of bases and anions and to result in modulating absorption and emission properties of the complexes.

π-Conjugated chelating polymers such as poly(2,2′-bipyridine-5,5′-diyl), poly(1,10-phenanthroline-3,8-diyl), and salophen polymers have been prepared by organometallic polycondensations. The obtained polymers form metal complexes with various metal species such as [Ru(bpy)2]2+ and CuCl2. Metal complexes of π-conjugated ligands are also polymerized by dehalogenative organometallic polycondensations. Some of the metal complexes of π-conjugated polymers exhibit electrical conducting nature and show catalytic activity for redox reactions.

Polycarbonates (PCs) were prepared by oxidative carbonylation of bisphenol A and carbon monoxide, using a Pd-polybipylidyl complex, Pd-polyvinylpyridine complex, smectite-supported Pd complex, or hydrotalcite-supported Pd complex as a heterogeneous Pd catalyst to separate the PC solution and the Pd catalyst after the reaction. Propylene carbonate was used as a halogen-free solvent. When Co(OAc)2·4H2O was used as the inorgano-redox catalyst, all of the Pd compounds gave a good PC yield with the recycling potential of the catalyst. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

A series of π-conjugated poly(aryleneethynylene)s (PAEs) containing two or three different arylene units in the main chain have been prepared by palladium-catalyzed coupling reactions. The PAEs consist of 2,5-dihexyloxy-1,4-phenylene diethynylene (–C C–C 6 H 2 (OC 6 H 13 ) 2 - p -C C–; C 6 H 13 = hexyl) units with alternating arylene (–Ar–) units. Various kinds of arylenes, including 9,10-dihydrophenanthrene-2,7-diyl (Phen), pyridine-2,5-diyl (Py), thiophene-2,5-diyl (Th), anthracene-9,10-diyl (Ant), and 2,1,3-benzothiadiazole-4,7-diyl (BTdz), are used as the –Ar– units. The obtained PAEs were soluble in organic solvents by virtue of the attached hexyloxy side chains, and were characterized by NMR, IR, GPC, and UV–vis absorption and photoluminescence (PL) spectroscopy. The cooperation of different polymer segments induces variations in the electronic structure of the PAEs that show π–π∗ absorption peaks in the range of 380–530 nm and PL emission peaks in the range of 430–610 nm with quantum yields of 5–55% in their solutions. The UV–vis and PL peaks of the PAEs shifted to a longer wavelength in films and in colloidal solutions, indicating the occurrence of intermolecular electronic interactions by aggregation. In Ant-containing PAEs, the PL of the polymer chain was entirely replaced with a red-shifted PL emission assignable to the Ant segments due to intramolecular energy transfer.

Solid-state structures of regioregulated poly(3-hexylthiophene) (P3HT) and poly(3-butylthiophene) (P3BT) were investigated using Fourier transform infrared absorption (FT-IR) spectroscopy. This study revealed that a twist glass transition of thiophene twisting for P3HT exists around 300 K ( T gp). Additionally, the influence of annealing on population of glassy crystal, crystal, and plastic crystal phases was explored. The annealed sample is dominated by plastic crystal phase, and this phase increases with annealing temperature below T gp. The frustration against crystallization in P3HT is weaker than that in P3BT. Consequently, the plastic crystal phase is formed as a dominant structure, whereas P3BT forms both a well-defined crystal in the conventional sense and glassy crystal.

π-Conjugated polymers are electrically conductive and light-emitting. They are film-forming, and their films possess flexibility and thermostability. They are attracting much attention as future materials for electronic and optical devices. Various π-conjugated conductive polymers have been synthesized via organometallic polycondensations mediated by organotransition metal complexes, and their applications to thin-film-transistors (TFT), organic-light-emitting diodes (OLED), photovoltaic cells, etc. are actively researched.In this chapter, we describe synthetic methods of π-conjugated conductive polymers using organometallic polycondensations. For example, Ni (0) complex-promoted dehalogenative polycondensation of dihaloaromatic compounds X-Ar-X affords poly(arylene)s —(Ar)n—, and Pd-catalyzed polycondensation gives poly(arylene-ethynylene)s, etc. Applications of conducting polymers to organic-thin-film-transistors and organic-light-emitting diodes are also described.

The optical properties of π-conjugated polymers based on 9,10-dihydrophenanthrene units, such as optical absorption and photoluminescence (PL), were studied. The electronic energy structures were determined by optical measurements. Strong PL with high quantum efficiency was clarified in the films, and photo-pumped multimode blue laser emission was demonstrated from cylindrical microcavities with the polymer thin film fabricated inside the optical capillary tube.

Preparation of New π-Conjugated Thiophene-Pyrrole Copolymers Having Ethynyl Substituents at the N -Position of Pyrrole

By various measuring techniques, dynamic properties can beobserved over the wide range of frequencies from picosecondsto minutes.Recently, a regioregulated -electron conjugated polyhet-erocyclic with five-membered ring, poly(4-alkylthiazole-2,5-diyl) (P4RTz), has beeen synthesized via dehalogenativeorganometallic polycondensation.

application/pdf, The cyclopalladation of 3,5-bis(diphenylphosphinothioyl)pyridine afforded new κ3S,C,S-pincer palladium complexes with a σ-bond between Pd and 4C of the centered 3,5-pyridinediyl unit. By utilizing the quaternization and complexation ability of the pyridine imine nitrogen (Npy) atom, various new pincer-type complexes, including hetero-binuclear complexes, have been synthesized.

Head-to-head type poly(3-(1-dodecynyl)thiophene-2,5-diyl), HH-P3(C CDec)Th, formed a well aligned structure in its cast film, and UV–vis absorption peak of the cast film showed a large shift by about 110 nm to a longer wavelength from that (518 nm) observed in solution. Under high pressure HH-P3(C CDec)Th exhibited clear piezochromism; the UV–vis absorption peak at about 605 nm observed under atmospheric pressure shifted to 672 nm under 10.71 GPa, suggesting an increase in electronic interaction between the polymer molecules under high pressure. The π–π ∗ transition energy decreased by 0.028 eV/GPa in the range of 0–5.2 GPa.

A soluble charge-transfer type poly(aryleneethynylene), PAE-AzaBzTdz, consisting of a highly electron-accepting azabenzothiadiazole unit was prepared in 99% yield by palladium-catalyzed polycondensation between 4,7-dibromo-2,1,3-azabenzothiadiazole (Br2-AzaBzTdz) and 1,4-diethynyl-2,5-didodecyloxybenzene. PAE-AzaBzTdz showed a number-average molecular weight, Mn, of 6000 in gel-permeation chromatography analysis and had good thermal stability as measured by TGA. UV–vis spectrum of PAE-AzaBzTdz exhibited an absorption peak at 529 nm in chloroform, and the absorption peak shifted to a longer wavelength (601 nm) in film. Addition of MeOH to a CHCl3 solution of PAE-AzaBzTdz led to aggregation of the polymer to form stable colloidal particles. Results of filtration experiments using 0.2 and 0.02 μm membranes supported aggregation of the polymer. Addition of trifluoroacetic acid (TFA) to a chloroform solution of PAE-AzaBzTdz led to a red-shift of the UV–vis peak from 529 to 640 nm. An X-ray diffraction pattern of powdery PAE-AzaBzTdz indicated that the polymer assumed a layer-to-layer stacked structure with an interlayer distance of 3.4 A in the solid state. An X-ray diffraction pattern of cast film of PAE-AzaBzTdz revealed that the polymer molecules in the cast film were ordered on the surface of Pt plate with the dodecyl side chain oriented toward the surface of the Pt plate. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2975–2982, 2008

The S-methylation of a macrocyclic tetrathiolactam afforded a new macrocyclic thioimidate that exhibited good affinity toward metal ions. The molecular structures of the macrocyclic ligand and its metal complexes were determined by X-ray crystallography.

A new pincer ruthenium complex (1; [RuL1(tpy)](PF6); L1 = 1,3-di(2-imidazoline-2-yl)benzene, tpy = 2,2′:6′,2″-terpyridine) having a κ3NCN pincer ligand with two imidazoline units and related ruthenium complexes were synthesized and characterized. The imidazoline units of 1 were oxidized in air to give an imidazole-ligated pincer complex (2; [RuL2(tpy)](PF6); L2 = 1,3-di(2-imidazolyl)benzene). Results of the 1H NMR spectroscopic and cyclic voltammetric studies of the complexes indicate that the σ-donor character of the pincer ligand of 1 induces the Ru-promoted oxidative dehydrogenation of coordinated imidazoline moieties to imidazole units with oxygen in air.

Preparation of Soluble Polypyrrole with -C≡C- p -C 6 H 4 -hexyl Side Chains at the N -Position and Its Self-assembling Behavior