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A series of novel coronene-based fluorescent materials have been synthesized through well-defined protocol from 1,2-dimethoxybenzene, with the key steps including Suzuki–Miyaura coupling and oxidative cyclodehydrogenation with ferric chloride. Fluorescence spectra investigations proved that they have emissions in the range λ 460-470 nm with excitation wavelength at λ 373 nm. It is found that different chromophores from substituents can significantly enhance the fluorescence intensities, which paves a new way of application of these materials in various fields.

1,1′-Bichrysene-2,2′-diol and its thiophene analogs, 6,6′-biphenanthro-[1,2- b]thiophene-7,7′-diols, as a series of novel π-expanded chrysene-/phenanthro[1,2- b]thiophene-based axially chiral molecules are synthesized from 1,1′-bi-2-naphthols with key steps including a Suzuki coupling, a Wittig reaction, and acid-mediated cyclization.

Supplemental material, 3.SI-Proof-An_SJ for Novel π-expanded chrysene-based axially chiral molecules: 1,1′-bichrysene-2,2′-diols and thiophene analogs by Shujie An, Guofeng Tang, Yaling Zhong, Li Ma and Qiancai Liu in Journal of Chemical Research

Four organic dyes based on indolo[3,2,1-jk]carbazole (IC-1, IC-2, IC-3, and IC-4) with different π-bridges (benzene ring and thiophene ring) are used for dye-sensitized solar cells (DSSCs) to investigate the effect of π-bridge on their photovoltaic performance. The introduction of thiophene ring as π-bridge (the dye IC-2) greatly improves the cell performance compared to benzene ring. The increasing conjugation length of the molecules decreases the performance of DSSCs. The best performance of DSSC based on IC-2 is obtained with a Voc of 0.66 V and a conversion efficiency of 3.68%. The poor performance of DSSCs based on IC-1 and IC-3 which contains only benzene ring as the π-bridge can be attributed to poor spectral coverage and higher electron charge transfer resistance as evaluated from EIS studies.

A new efficient synthesis of indolo[3,2,1-jk]carbazoles by the palladium-catalyzed cyclization of N-(2-bromoaryl)carbazoles is described. The reaction involves intramolecular C–C bond formation, coupled with the cleavage of a C–X bond and a C–H bond on carbazole ring. Substitutions on N-aryl core with either electron-donating or electron-withdrawing groups are introduced, and different reaction factors for cyclization are evaluated.

A series of 2-amino-4-aryl-6-(9,9′-spirobifluoren-2-yl)pyrimidines have been synthesized by the reaction of guanidine and chalcones under basic conditions. The physical and optical properties indicated that these compounds generally show good blue light emissions and excellent thermal stabilities. Intermolecular hydrogen bonds and interactions have strong influences on their properties.

Novel indeno-spirobifluorene and dispirobifluorene derivatives were synthesized and characterized. Their two positional isomers were unambiguously determined by X-ray crystallography. Preliminary investigations indicated that these indeno-spirobifluorene and dispirobifluorenes showed blue fluorescence with good quantum yields (Φ>60%) and excellent thermal stabilities.

Seven kinds of lanthanocene complexes were prepared by the reaction of tridentate Schiff base | N-(2-methoxyphenyl)salicylideneamine with tris(cyclopentadienyl) lanthanide tetrahydrofuranate or bis (cyclopentadienyl) lanthanide chloride tetrahydrofuranate in THF. All the complexes were characterized by MS, EA and IR respectively. The structure of |Cp2LnC14U13NO2) Ln = Sm, Dy, Y, Er| (1–4) was further confirmed by X-ray determination of Cp2Sm(C14H13NO2) (1) which indicates that the complex is monomeric in which central metal is coordinatively saturated by two cyclopentadienyl rings, two oxygens and one nitrogen of the ligand. The isomerization of 1,5-hexadiene explains that complexes (1–4) isomerize this monomer into a mixture of 1,4-hexadiene, 2,4-hexadiene, 1,3-hexadiene, methylenecyclopentane and methyl–cyclopentene. Similarity complexes |CpLn(a) C14 H13NO2) (THF) (Ln=Sm, Dy, Y, Er)| (5–7) polymerize methyl-methacrylate (MMA) to give polyMMA (PMMA) in 51.8% yield and high molecular weight (274 × 103), which shows narrow molecular weight distributions and partially syndiotactic.

Two types of sandwich complexes (η5-MeOCH2CH2C9H6) Ln (η8-C8H8) (THF)n [Ln=La (1), Nd(2), n=0; Sm(3), Dy (4) and Er (5). n = l] and (η5-C4H7OCH2C9H6)Ln(η8-C8H8) (THF) [Ln = La (6), Nd(7). Sm(8). Dy (9) and Er (10)] were synthesized by the reactions of LnCl3 with equivalent mole of K2C8H8, followed by treatment with corresponding potassium salt of ether-substituted indenide. The molecular structures of 3 and 8 were determined by single crystal X-ray diffraction. (η5 -MeOCH2CH2C9H6) Sm (η8-C8H8) (THF) (3) monoclinic. Pt1/c, a = 1.4793(3) nm, b = 0.8716 (2) nm, c = 1.6149 (3) nm, β = 98. 17(3), V = 2.0612(7) nm3, Z = 4, R(F)=0.0362. (η5-C4H7OCH2C9H6)Sm(η8-C8H8)(THF) (8) orthorhombic. p212121. a = 0.8754(2) nm, b = 1.1000(2) nm, c = 2.3117 (5) nm, V = 2.2260(8) nm3, Z=4, R(F) =0.0497.

Synthesis of 5,7-phenylquinoline from the Skraup reaction of m-terphenyl-amine and glycerol in the presence of acid is reported. Further reaction of 5,7-diphenyl-quinoline with phenyl lithium prepared in situ led to the formation of 2,5,7-triphenyl-quinoline. All of the products and their intermediates were characterized and the UV-Vis and photo-luminescence (PL) spectra of m-terphenylamine, 5,7-diphenylquinoline and 2,5,7-triphenylquinoline are also reported.

Title compounds (III) are easily and simply synthesized with low catalyst loading and without protection of the amino group.

Reaction of (S)-4-carbomethoxy-2-phenyl-2-oxazoline with Pd(OAc)2 leads to the formation of the ortho-palladated complex (S,S)-di-μ-(acetate)-bis{2-[2-(4-carbomethoxy)oxazolinyl]phenyl-C,N}dipalladium(II) (1). In the presence of water, this complex reacts with methylparathion to produce p-nitrophenol as well as two oxazoline palladium dimethylthiophosphate complexes (2 and 3), which have been observed in solution by 31P NMR. This reaction is accompanied by racemization of the oxazoline ligand and ultimately produces the dinuclear complex (R,S)-di-μ-(dimethylthiophosphate-S,S)-bis{2-[2-(4-carbomethoxy)oxazolinyl]phenyl-C,N}dipal-ladium(II) (4), which features bridging dimethylthiophosphate ligands. At pH 9−10, complex 1 serves as a precatalyst for the hydrolysis of methylparathion. The reaction rate has a first-order dependence in substrate and palladium catalyst with a second-order rate constant of 726 (± 30) M-1 s-1 at pH 9.0.

Starting materials (I) are readily prepared by condensation of 1,3-diarylacetones with ninhydrin.

LnCl3 reacted with K2C8H8 in THF in the ratio 1:1 at room temperature and formed (C8H8)LnCl·nTHF, which was then treated with RCpK–THF (RCp=MeOCH2CH2C5H4 or C4H7OCH2C5H4) to yield the title complexes (η5-RCp)Ln(η8-C8H8)(THF) (Ln=Nd (1) and Sm (2), RCp=MeOCH2CH2C5H4; Ln=La (3), Nd (4) and Sm (5), RCp=C4H7OCH2C5H4). The crystal structures of complexes 1 and 3 were determined by X-ray diffraction and revealed that the oxygen atoms of the ether group on the cyclopentadienyl ring is coordinated to the central metal atom. The central lanthanum atom is in a distorted tetrahedral geometry. The average bond distances Nd–C(η8) and Nd–C(η5) are 2.697(2) and 2.749(2) A, respectively, while the Nd–O(THF) and Nd–O(η1) distances are 2.580(1) and 2.619(1) A, respectively. The average bond lengths La–C(η5) and La–C(η8) are 2.842(7) and 2.740(8) A, respectively. The La–O(THF) and La–O(η1) distances are 2.607(4) and 2.633(4) A.

LnCl3 reacted with three equivalents of methoxyethylcyclopentadienyl potassium in tetrahydrofuran (THF), followed by treatment with trans-(±)-2,2′-[1,2-cyclohexanediylbis(iminomethyl)] diphenol gave a binuclear mono(methoxyethylcyclopentadienyl)samarium complex [(η5:η1-Cp′Sm] [(μ:η-OC20H20N2O)]2[η5-Cp′Sm] (1), and bis(methoxycyclopentadienyl) ytterbium, [Cp2′Yb]2(OC20H20N2O) (2) (Cp′=MeOCH2CH2C5H4). The X-ray determination of complex 1 shows that the molecule is a dimer, in which two (MeOCH2CH2C5H4)Sm(μ:η1-OC20H20N2O) units are connected to two bridging oxygen atoms of Schiff base ligands. The average Sm–C distance is 2.769(7) A, while that of Sm–O (bridging Schiff base oxygens) is 2.401(4) A. Further studies on the reaction of Cp2′DyCl (Cp′H=MeOCH2CH2CpH) with the disodium salt of trans-(±)-2,2′-[1,2-cyclohexanediylbis(iminomethyl)]diphenol resulted in an analogue of complex 1: [(MeOCH2CH2C5H4)Dy(OC20H20N2O)]2 (3). However, Cp2″DyCl reacted with disodium salt of trans-(±)-2,2′-[l,2-cyclohexanediylbis(iminomethyl)]diphenol to give rise to the isolation of dinuclear bis(tetrahydrofurfurylcyclopentadienyl) dysprosium complex with one molecular ligand, (Cp2″Dy)2(OC20H20N2O) (4) (Cp″H=C4H7OCH2C5H5).

SmCl3 reacted with CpNa (Cp = Cyclopentadienyl) in the ratio of 1 : 3 in THF, which then was reacted with (S)−(+)-N-1-(phenylethyl)salicylideneamine/toluene to yield the title complex, The X-ray crystal structure determination of the title complex reveals that 1 is a dimer with intramolecular CC bond formation and hydrogen transfer, which leads to the configuration turnover of the carbon atom at the benzyl position of the ligand, while those of the newly formed asymmetric centers may have either R or S type configurations.

Cp2SmCl(THF) reacts with 0.5 equivalent disodium salts of trans-(+/-)-N,N'-bis(salicylidene)-1,2-cyclohexanediamine give the title complex [(eta(5)-C5H5)Sm(mu-OC20H20N2O)](2)(mu-THF)(THF)(2) (1). X-ray crystal determination shows that the molecule is a dimer, in which two (eta(5)C(5)H(5))Sm(mu-OC20H20N2O) units are connected via a THF oxygen and two bridging oxygen atoms of Schiff base ligands. The average Sm-C distance is 2.78(7) Angstrom, while those of Sm-O (bridging THF oxygen) and Schiff base oxygens are 2.79(3) and 2.43(4) Angstrom; respectively. (C) 1998 Elsevier Science Ltd. All rights reserved.

A novel approach to the title compounds (II), required as electron-donating components in material chemistry, is developed via C—X/C—H coupling of N-(2-bromoaryl)-substituted carbazoles.

A series of 2-amino-4-aryl-6-(9,9′-spirobifluoren-2-yl)pyrimidines have been synthesized by the reaction of guanidine and chalcones under basic conditions. The physical and optical properties indicated that these compounds generally show good blue light emissions and excellent thermal stabilities. Intermolecular hydrogen bonds and interactions have strong influences on their properties.

The acid-promoted mono- or dialkylation of carbazoles (I) with fluorenol (II) followed by palladium-catalyzed intramolecular arylation of intermediates (III) and (V) gives rise to novel fluoradenes (IV) and (VI).

A novel approach towards 7b-aryl-indeno[1,2,3-jk]fluorene based on a nitrogen-containing core is reported. The acid-promoted Friedel-Crafts reaction of 9-(2-bromophenyl)-9-fluorenol with carbazole, triphenylamine or triindole afforded 9-(2-bromophenyl)fluorenyl-carbazole, -triphenylamine and -triindole derivatives, which were subsequently converted to 7b-aryl-fluoradenes via palladium-catalyzed intramolecular C-H direct arylation as a key step.

The diindenocarbazole derivatives are synthesized by the reaction of 2,7-dibromo-9-hexylcarbazole with benzoyl chloride under Friedel-Crafts conditions, followed by Wolff-Kishner-Huang reduction to produce 3,6-dibenzyl-2,7-dibromo-9-hexylcarbazole, which was cyclized to form bis(indeno)-9-hexylcarbazole by palladium-catalyzed double intramolecular arylation. The diindeno-carbazole was further converted into fully alkylated compounds.

Reaction of YbCl3 with 3 equimolar CpNa (Cp = cyclopentadienide) in THF, followed by treatment with trans-(+/-)-N,N'-bis(salicylidene)-1,2-cyclohexanediamine led to the isolation of first mono(cyclopentadienyl) lanthanide Schiff base complex, [(eta(5)-C5H5)Yb(mu-OC20H20N2O)](2) (mu-THF)(THF) (1). The molecular structure of 1 shows that it is a dimer in which the two [(eta(5)-C5H5)Yb(mu-OC20H20N2O)] units connecting via a bridging THF oxygen and two bridging oxygen atoms from Schiff base ligands. (C) 1998 Elsevier Science S.A.

A concise and facile synthesis of 2,8-disubstituted dithieno[3,2-b:6,7-b]fluorenes starting from 2,7-dihydroxyfluorenone is reported. The key step involved is the tandem annulation–reduction of a 3,6-dichloro-2,7-di(alkynyl)fluorenone using Na2S·9H2O as a sulfur surrogate and reductant. The final dithiophene-fused fluorenes are obtained in reasonable yields (23–43%).

A novel synthetic route to fluorene- and spirobifluorene-fused thiophenes is explored by starting with ninhydrin. The Diels-Alder cycloaddition was employed to construct the key intermediate

The title compound, [Pd(2)(C(9)H(11)ClN)(2)Cl(2)], consists of two Pd atoms which are bridged by two Cl atoms, forming a centrosymmetric binuclear complex with a square-planar coordination for each of the Pd atoms. The Pd atom is chelated by one N and one C atom from a 4-chloro-2-(dimethyl-amino-meth-yl)phenyl ligand, forming a five-membered ring (N-Pd-C-C-C). In the crystal structure, weak C-H ⋯Cl hydrogen bonds link the mol-ecules in rows.

The diindenocarbazole derivatives are synthesized by the reaction of 2,7-dibromo-9-hexylcarbazole with benzoyl chloride under Friedel-Crafts conditions, followed by Wolff-Kishner-Huang reduction to produce 3,6-dibenzyl-2,7-dibromo-9-hexylcarbazole, which was cyclized to form bis(indeno)-9-hexylcarbazole by palladium-catalyzed double intramolecular arylation. The diindeno-carbazole was further converted into fully alkylated compounds.

Reaction of tris(cyclopentadienyl)lanthanide with the tridentate Schiff base N-1-(ortho-methoxyphenyl)salicylideneamine in THF at room temperature affords the isolation of monomeric lanthanocene Schiff base complexes, (η5-C5H5)2Ln (OC14H13NO) (Ln=Sm (1), Er (2), Dy (3), Y (4)), which have been characterized by elemental analysis and mass spectra. The X-ray determination of 1 indicates that the complex is monomeric in which the metal center is coordinatively saturated by two cyclopentadienyl rings and two oxygens and one nitrogen from the Schiff base ligand. The average Sm–C bond distance is 2.723(7) A, while those of the metal center to the Schiff base oxygens and nitrogen atoms are 2.232(4), 2.572(4) and 2.534(4) A, respectively.

Complexes (Salpren(tBu,tBu))Y[N(SiHMe2)2](thf) and (SALEN(tBu,tBu))La[N(SiHMe2)2](thf) (SALEN(tBu,tBu) = Salcyc(tBu,tBu) and Salpren(tBu,tBu)) were prepared from Ln[N(SiHMe2)2]3(thf)2 and H2SALEN(tBu,tBu). The yttrium complex was characterized by X-ray crystallography revealing intrinsic solid-state structural features: the metal centre is displaced by 1.05 angstroms from the [N2O2] least squares plane of a highly bent Salpren(tBu,tBu) ligand (angle(Ph,Ph) dihedral angle of 80.4(1) degrees ) and is coordinated asymmetrically by the silylamide ligand exhibiting one significant Y---(HSi) beta-agostic interaction (Y-N1-Si1, 106.90(9) degrees; Y---Si1, 3.2317(6) angstroms). Complexes (SALEN(tBu,tBu))Ln[N(SiHMe2)2](thf)n (n = 1, Sc; n = 2, Y, La) react with ammonium tetraphenylborate to form the ion pairs [(SALEN(tBu,tBu))Ln(thf)n][BPh4]. The cationisation was proven by X-ray crystal structure analyses of [(Salpren(tBu,tBu))Sc(thf)2][B(C6H5)4].2(thf) and [(Salpren(tBu,tBu))Ln(thf)3][B(C6H5)4].4(thf) (Ln = Y, La), showing an octahedral and pentagonal-bipyramidal coordination geometry, respectively.