Two novel lumophores based on aluminum and zinc metallo-8-hydroxyquinolates have been prepared as electroluminescent materials, and their absorbance, photoluminescence, and electroluminescence properties compared with unsubstituted versions of these same complexes. 8-Hydroxy-5-piperidinylquinolinesulfonamide (1) was synthesized in order to add an electron-withdrawing substituent at the 5-position in 8-hydroxyquinoline, increasing the solubility of the corresponding metal quinolate complexes in nonpolar solvents, and producing a blue-shift in the emission wavelength maximum, relative to complexes formed from the unsubstituted compound. The aluminum complex (Al(QS)3) and the zinc complex (Zn(QS)2) of 1 were compared with the aluminum and zinc complexes of unsubstituted 8-hydroxyquinoline (AlQ3 and ZnQ2), both as solutions and as pure thin films, or as poly(N-vinylcarbazole) (PVK) thin films doped with the metal quinolates. Ultraviolet photoelectron spectroscopy data are presented to assist in estimating the energies of the highest occupied molecular orbitals (HOMO) of AlQ3, ZnQ2, Al(QS)3, and Zn(QS)2. Electroluminescence data shows that ITO/Al(QS)3−PVK/aluminum and ITO/Zn(QS)2−PVK/aluminum devices exhibit good diode-like electrical behavior. Electroluminescence spectra mimic the photoluminescence spectra for all complexes.

Solution electrochemical studies have been conducted of the principle lumophores, dopants, and hole-transport agents of aluminum-quinolate(Alq3)-based organic light-emitting diodes (OLEDs) along with the characterization of their electrogenerated chemiluminescence (ECL). In acetonitrile/benzene solvent mixtures, Alq3 shows single one-electron reduction and oxidation processes, with a separation between the first oxidation and first reduction potentials, ΔE electrochemical = 3.03 V, close to the estimates of energy difference between HOMO and LUMO levels obtained from absorbance spectra of thin films of Alq3, ΔE optical = 3.17 eV. A new sulfonamide derivative of Alq3, (Al(qs)3), showed a positive shift (ca. 0.32 V) in the first reduction potential versus the parent molecule, and resolution of the overall reduction process into three successive, chemically reversible, one-electron reductions. Two successive one-electron oxidations are seen for 4,4‘-bis(m-tolyphenylamino)biphenyl (TPD), a hole-transporting material in many bilayer OLEDs, and for TPDF2, a fluorinated version of TPD, with TPDF2 oxidation occurring 0.1 V positive of that for TPD. Electrogenerated chemiluminescence reactions (Alq3 -•/TPD+• (or TPDF2 +•) and Al(qs)3 -•/TPD+• (or TPDF2 +•)) were found to produce emission spectra from Alq3*s or Al(qs)3*s states which were nearly identical to those seen from OLEDs based upon these molecules. Emission intensities increased with the increasing potential difference between the relevant redox couples. The diisoamyl derivative of quinacridone (DIQA), a quinacridone dopant for certain Alq3-based OLEDs, undergoes two successive one-electron reductions and two successive one-electron oxidations. The ECL reactions DIQA-•/DIQA+•, DIQA+•/Alq3 -•, DIQA+•/Al(qs)3 -•, DIQA-•/TPD+• and DIQA-•/TPDF2 +• all produce the same singlet emissive state, DIQA*s, and the same emission spectral response seen in quinacridone and DIQA-doped OLEDs.

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A survey of the spontaneous reactions of electrophilic olefins and nucleophilic olefins is presented as an area in which organic chemistry merges with polymer chemistry. The products include both small molecules and polymers, arising via tetramethylene biradical zwitterions that can cyclize or initiate polymerizations. Electrophilic tri-and tetrasubstituted olefins are particularly useful in delineating the transition from radical chemistry to ionic chemistry. A periodic table embodying these results enables predictions. Charge-transfer complexes, although observed in many of these reactions, play no significant role. Various aspects arising from these investigations include new cationic initiators, Lewis acid catalysis, quinodimethane chemistry, and photochemistry.

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An experimental study of the photorefractive effect in a polymeric material containing carbazole and the second-order tricyanovinylcarbazole moieties as a side chain is presented. This polymeric system exhibits intrinsically both photoconductivity and the electro-optic effect. Absorptive and photorefractive gratings have been evidenced by four-wave-mixing experiments and electro-optic measurements. The properties of the photorefractive gratings are studied by investigating the electric-field dependence of the diffraction efficiency. The dynamics of the erase-write behavior of the gratings, as well as permanent photobleaching of the polymer, are described.

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A novel synthetic route to poly(quinone imines) has been developed. Reaction of anthraquinone (AQ) with aromatic diamines in the presence of titanium tetrachloride and 1,4-diazabicyclo-[2.2.2]octane (Dabco) as base in refluxing chloroor o-dichlorobenzene led to high molecular weight polymers with the poly(quinone diimine) structure. Polymerization of AQ with methylene-4,4'-dianiline resulted in a mixture of high molecular weight polymer (Aiw 15 000) and oligomeric macrocycles. The polymerization of AQ was also accomplished with 4,4'-oxy-and 4,4'-thiodianiline, as well as with p-phenylenediamine. The latter polymer is the dibenzo analog of the pemigraniline base form of polyaniline. teri-Butylanthraquinone was also successfully used as a comonomer with the various aromatic diamines. All these polymers are red in color, soluble in organic solvents, and film-forming. Polymerizations of the aromatic diamines with heterocyclic-substituted benzoquinones, such has benzo[l,2-5:4,5-6']dithiophene-4,8-dione, 2,2'-dialkylbenzo [l,2-d:5,4-d']dioxazole-4,8-dione, and NjV',2,2'-tetraalkylbenzo- [l,2-d:5,4-d']imidazole-4,8-dione, were also investigated.