Reactivity of Organolithium Reagents to 2,3,4,5-Tetraphenylcyclopentadienone and Crystal Structures of Addition Products

The conjugate addition reactions of four organolithium reagents to 2,3,4,5-tetraphenylcyclopentadienone (tetracyclone) were investigated to reveal the reactivity of organolithium reagents to tetracyclone. The results show that 1,2-addition products 2,3,4,5-tetraphenyl-1-(2-thienyl)-2,4-cyclopentadien-1-ol(1), 1-n-butyl-2,3,4,5-tetraphenyl-2,4-cyclopentadien-1-ol(2) and 1,2,3,4,5-pentaphenyl-2,4-cyclopentadien-1-ol(3) were synthesized in excellent yields while tetracyclone reacted with 2-thienyllithium, n-butyllithium and phenyllithium, respectively. Interestingly, three 1,2-, 1,4- and 1,6-addition isomers 1-tert-butyl-2,3,4,5-tetraphenyl-2,4-cyclopentadien-1-ol(4), 4-tert-butyl-2,3,4,5-tetraphenyl-2-cyclopenten-l-one(5) and 2-tert-butyl-2,3,4,5-tetraphenyl-3-cyclopenten-l-one(6), were simultaneously obtained by the conjugate addition reaction of tert-butyllithium with larger steric hindrance to tetracyclone. Compounds 1-6 were characterized by ¹H and ¹³C NMR spectra, Fourier transform infrared(FTIR) spectra and mass spectra(MS). The crystal and molecular structures of compounds 1, 2 and isomers 5, 6 were determined by X-ray single crystal diffraction technique. The results imply that the steric hindrance of tert-butyllithium probably play a key role in controlling the conjugate addition reaction. The conjugate addition mechanism of organolithium reagents to tetracyclone was proposed.     

Dissociation of the disilatricyclic diallylic dianion [(C4Ph4SiMe)2]-2 to the silole anion [MeSiC4Ph4]- by halide ion coordination or halide ion nucleophilic substitution at the silicon atom

The reductive cleavage of the Si-Si bond in 1,1-bis(1-methyl-2,3,4,5-tetraphenyl-1-silacyclopentadiene) [(C(4)Ph(4)SiMe)(2)] (1) with either Li or Na in THF gives the silole anion [MeSiC(4)Ph(4)]- (2). The head-to-tail dimerization of the silole anion 2 gives crystals of the disilatricyclic diallylic dianion [(C(4)Ph(4)SiMe)(2)]-2 (3). The derivatization of 3 (crystals) with bromoethane (gas) under reduced pressure provides [(MeSiC(4)Ph(4)Et)(2)] (4) quantitatively. The reverse addition of 3 in THF to trimethylsilyl chloride, hydrogen chloride, and bromoethane in THF gives 1-methyl-1-trimethylsilyl-1-silole [Me(3)SiMeSiC(4)Ph(4)] (6), 1-methyl-2,3,4,5-tetraphenyl-1-silacyclo-3-pentenyl-1-methyl-1-silole [C(4)Ph(4)H(2)SiMe-MeSiC(4)Ph(4)] (7), and 1-methyl-2,5-diethyl-2,3,4,5-tetraphenyl-1-silacyclo-3-pentenyl-1-methyl-1-silole [C(4)Ph(4)Et(2)SiMe-MeSiC(4)Ph(4)] (8), respectively. The reaction products unambiguously suggest that the silole anion [MeSiC(4)Ph(4)]- is generated by coordination of the chloride ion at the silicon atom in 3 or by the nucleophilic substitution of either chloride or bromide ion at one of two silicon atoms in 3. The quenching reaction of 3 dissolved in THF with water gives 1,2,3,4-tetraphenyl-2-butene, the disiloxane of 1-methyl-2,3,4,5-tetraphenyl-1-silacyclo-3-pentenyl [O(MeSiC(4)Ph(4))(2)] (10) and methyl silicate.     

Solid state photochromism of 2,4,4,6-tetraphenyl-4H-pyran and 1,4-dihydropyridine derivatives

Results of a study on the photochromic behaviour of various 2,4,4,6-tetraphenyl-4H-pyrans (1), 2,4,4,6-tetraphenyl-1,4-dihydropyridines (2 and 3) and 1,2,4,4,6-pentaphenyl-1,4-dihydropyridines (4) are reported. Most investigated materials undergo a photochromic change in the solid state after illumination with UV light. The maxima of the new absorption bands are located in the range 545–630 nm, depending on the chemical structure of the substituents. The non-exponential time dependence of photochromic decolouration of the model compound, 1-methyl-2,4,4,6-tetraphenyl-1,4-dihydropyridine (3a), is analysed in terms of a dispersive first-order reaction, i.e. is described by the formula exp(−t), where is the dispersion parameter.     

Structural and spectral studies of palladium(II) and platinum(II) complexes derived from N,N,N,N-tetradentate macrocyclic ligands

Palladium(II) and platinum(II) complexes having the general composition [M(L)] X2 (where M=Pd(II) and Pt(II), L=3,4,12,13-tetraphenyl-2,5,11,14,19,20-hexaaza tricyclo [13.3.1.1.(6-10)] cosa-1(19), 2,4,6,8,10,(20),11,13,15,17-decaene (L1); 3,4,13,14-tetraphenyl-2,5,12,15-tetraaza tricyclo [11,0,0,(6-11)] cosa-1(16),2,4,7,9,6(11),12,14,17, 19-decaene (L2); 2,3,8,9-tetraphenyl-1,4,7,10-tetraaza cyclododeca-1,3,7,9-tetraene (L3) and X=Cl(-)) have been synthesized. The ligands were characterized on the basis of elemental analyses, IR, 1H NMR and EI mass spectral studies while that of the complexes were characterized on the basis of elemental analyses, molar conductance measurements, magnetic susceptibility measurements, IR, and electronic spectral techniques. All the complexes were found to be diamagnetic. The structures consist of monomeric units in which the Pd(II) and Pt(II) atoms exhibit square planar geometry.     

1,4-二锂四苯基-1,3-丁二烯与卤代烃反应的研究(Ⅱ)——与溴甲烷的反应

1,4-二锂四苯基-1,3-丁二烯与溴甲烷反应生成顺,顺-和顺,反-2,3,4,5-四苯基-2,4-己二烯。其分子结构和比例由MS、NMR及X射线单晶分析所确定。讨论了产物的生成途径。     

Study of radical generated from coumarin dye-sensitized photo-initiator systems in high-speed photopolymer coating layers using laser flash photolysis

Radical generation from photoinitiation systems containing carbonylbiscoumarin dye with a radical-generating reagent, 3,3′-carbonylbis[7-(diethylamino)-2H-1-benzopyran-2-one] (KCD-DA), with 2,2′-bis(2-chloro-phenyl)-4,4′5,5′-tetraphenyl-1, 1′-bi-1H-imidazole (BI) in a poly(methyl methacrylate) film has been investigated by laser flash photolysis using a total reflection cell. Imidazolyl radical (Im·) was predominantly generated from carbonylbiscoumarin triplet-sensi-­tized decomposition of BI, the quantum yield, Φ^o_Im· of Im· at an infinite concentration of BI was measured, Φ^o_Im· = 1.3. The high quantum yield, Φ^o_Im·, implies an efficient KCD-DA triplet-sensitized photoinitiation system containing BI. Copyright © 1998 John Wiley & Sons, Ltd.     

Theoretical insight into pyrrole inversion and planarity in 5,10,15,20-tetraphenylsapphyrin and 5,10,15,20-tetraphenyl-26,28-diheterosapphyrins with two O, S, or Se atoms

Density functional calculations at the B3LYP/6-31+G(d) (LACVP(D) for Se) theory level have been carried out on 5,10,15,20-tetraphenylsapphyrin ( TPS), 5,10,15,20-tetraphenyl-26,28-dioxasapphyrin ( TP2OS), 5,10,15,20-tetraphenyl-26,28-dithiasapphyrin ( TP2SS), and 5,10,15,20-tetraphenyl-26,28-diselenasapphyrin ( TP2SeS). In agreement with experimental findings, our theoretical results show that TPS and TP2OS present an inverted conformation, whereas TP2SS and TP2SeS are more stable in the normal one. It was found that the relative stability of the normal and inverted conformers of the just mentioned sapphyrins correlates positevily with their degree of planarity and aromaticity, which depends on the size of the heteroatom, the steric repulsions produced by phenyl rings at the meso C atoms, and the network and nature of the bond critical points (BCPs) inside the macrocycle. These BCPs have been characterized by means of the AIM analysis and, some selected ones, by the changes in the total energy of significant fragments when distorted to avoid them.     

Copper(II) complexes of inverted porphyrin and its methylated derivatives

The inverted porphyrins 2-aza-5,10,15,20-tetraphenyl-21-carbaporphyrin (CTPPH2) and its methylated derivatives 2-aza-2-methyl-5,10,15,20-tetraphenyl-21-carbaporphyrin (2-NCH3CTPPH) and 2-aza-2-methyl-5,10,15,20-tetraphenyl-21-methyl-21-carbaporphyrin (2-NCH3-21-CH3CTPPH) stabilize the rare organocopper(II) complexes (CTPP)CuII (1), (2-NCH3CTPP)CuII (2), (CTPPH)CuIIX (3-X), (2-NCH3CTPPH)CuIIX (4-X) (X = Cl-, TFA), and (2-NCH3-21-CH3CTPP)CuIICl (5). The EPR spectra recorded for 1, 2, 4, and 5 revealed typical features diagnostic of the copper(II) electronic structure. The superhyperfine coupling pattern indicates a presence of three nitrogen donors in the first coordination sphere. An addition of HX acid to 1 and 2 to yield the species 3-X and 4-X. The reaction mechanism includes protonation of the inner C(21) carbon accompanied by an axial coordination of anion. Methylation of (2-NCH3CTPP)CuII (2) with methyl iodide resulted in formation of (2-NCH3-21-CH3CTPP)CuIICl (5) which implies an existence of a sigma-carbanion-copper(II) bond in 2. The 2H NMR investigations carried out for the pyrrole deuterated derivatives (CTPP-d7)CuII, (2-NCH3-21-CH3CTTP-d7)CuIICl, and the methyl deuterated (2-NCH3-21-CD3CTPP)CuIICl one confirmed independently the copper(II) electronic structure with the considerable dx2-y2 metal orbital contribution to the SOMO. The redox properties of copper(II) inverted porphyrins were studied by the cyclic and differential pulse voltammetry. The halfwave potentials indicate a metal-centered oxidation of 1 (390 mV) and 2 (343 mV). The dimethylated homologue 5 reveals the reduction process at -224 mV attributed to the CuII/CuI transformation.     

New method of synthesis of 1,1-bis(trialkylsilyl)- and bis(trialkylgermyl)germacyclopenta-2,4-dienes

The reactions of 1,1-dichloro-2,3,4,5-tetraphenyl-1-germacyclopenta-2,4-diene (1), magnesium, and R₃ECl (E = Si, Ge) under mild conditions (20 °C, THF) gave 1,1-bis(trimethylsilyl)-2,3,4,5-tetraphenyl-1-germacyclopenta-2,-4-diene (2a) and 1,1-bis(triethylgermyl)-2,3,4,5-tetraphenyl-1-germacyclopenta-2,4-diene (2b) respectively. The reaction is versatile and applies to the compounds R₃ECl (E = Si, Ge) that do not react with magnesium.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2234–2236, October, 2004.     

Cyclization of Ph2Si(NHNHMe)2. I. Reaction with n-BuLi/Ph2SiCl2 and ring rearrangement

Reaction of Ph₂Si(NHNHMe)₂ ( 1 ) with n-BuLi and Ph₂SiCl₂ in 1 : 2 : 1 ratio afforded 54% of 1,2,4-triaza-1-methyl-4-methylamino-3,3, 5, 5-tetraphenyl-3,5-disilacylopentane ( 2 ). In the presence of a catalytic amount of n-BuLi, 2 is rearranged to two isomers, 1,2,4,5-tetraaza-1,4-dimethyl-3,3,6,6-tetraphenyl-3,6-disilacyclohexane ( 3 ) and 1,2,4,5-tetraaza-1,5-dimethyl-3,3,6,6-tetraphenyl-3,6-disilacyclohexane ( 4 ), with 3 as the major product. The crystal structure of 3 reveals a twist-boat conformation of the Si₂N₄ ring [a = 10.691(4) Å, b = 13.178(4) Å, c = 17.812(3) Å, β = 95.11(7)°; monoclinic, P2₁/n; Z = 4], in which each N(Me) N(H) unit contains one pyramidal (NH) and one planar (NMe) nitrogen.     

The preparation of a series of 12-, 13- and 14-membered tetra-imine macrocycles and characterization of their copper(II) complexes

Summary The 12-, 13- and 14-membered tetraphenyl substituted macrocycles Ph₄[12]TIM (2,3,8,9-tetraphenyl-1,4,7,10-tetra-azacyclododeca-1,3,7,9-tetraene), Ph₄[13]TIM (2,3,8,9-tetraphenyl-1,4,7,10-tetra-azacyclotrideca-1,3,7,9-tetraene) and Ph₄[14]TIM (2,3,9,10-tetraphenyl-1,4,8,11-tetradeca-1,3,8,10-tetraene) were prepared and their copper(II) complexes characterised. Magnetic and spectroscopic measurements (i.r. and u.v.-vis.) are discussed. A variety of macrocyclic precursers (KIM = 1,2,8,9-tetraphenyl-3, 7-diaza-2,7-dione) and KIM-dioxime were also prepared and characterised.     

Fluorescent tricyclic β-azavinamidine–BF2 complexes

Boron trifluoride reacted with dipyrid-2-ylamine 6 , its N-methyl and 6,6′-dimethyl derivatives 8 and 10 , and 3,3′,5,5′-tetraphenyl-6-azapyrromethene 13 to give fluorescent β-azavinamidine (1,3,5-triazapenta-1,3-diene) dyes: 10-azapyridomethene–BF₂ complex 5 (λ_f 422 nm, λ_las 426 nm), its quaternary 10-methyl tetrafluoroborate and 4,6-dimethyl derivatives 9 (λ_f 362 nm) and 11 (λ_f 416 nm), and 1,3,5,7-tetraphenyl-8-azapyrromethene–BF₂ complex 17 (λ_f 696 nm). Treating 3,3′,4,4′-tetraphenyl-5,5′,6-trimethylpyrromethene (prepared in situ from ethyl 3,4-diphenyl-5-methylpyrrole-2-carboxylate in a reaction with acetyl chloride) with boron trifluoride gave 1,2,6,7-tetraphenyl-3,5,8-trimethylpyrromethene–BF₂ complex 21 . Absorption for the vinamidine chromophore differed from that for the β-azavinamidine chromophore by a hypsochromic shift of 86 nm in a comparison of pyridomethene–BF₂ complex 3 with its 10-aza derivative 5 and by a bathochromic shift of 105 nm in a comparison of the pyrromethene–BF₂ complex 20 with the 8-azapyrromethene–BF₂ complex 17 .     

Further insight into the coordination of 2,5-dicarbothioamidopyrroles: the case of Cu and Co complexes

The coordination chemistry of 2,5-dicarbothioamidopyrrole ligands, namely N2,N5-dibutyl-3,4-diphenyl-1H-pyrrole-2,5-bis(carbothioamide) and N2,N5,3,4-tetraphenyl-1H-pyrrole-2,5-bis(carbothioamide), has been investigated with Cu(II) metal centres by means of X-ray crystallography. This resulted in the formation of the expected planar S,N,S' coordinated complex for the former ligand and unexpected ring-closure reactions, with formation of benzothiazole sidearms, for the latter. Both Cu(II) and Cu(I), used in large excess, were found to favour the ring-closure reaction, although the structural characterisation of the resulting complexes contained only Cu(II) cations, with varying coordination geometries ranging from square planar and square-based pyramidal to tetrahedral. By repeating the reaction using a slight excess of Cu(II) (2?:?1) two more different structures were obtained where the metal was coordinated to the original ligand, N2,N5,3,4-tetraphenyl-1H-pyrrole-2,5-bis(carbothioamide), or to the mixed ligand where only one of the thioamide substituents had converted to a benzothiazole. The essential role of Cu for the ring closure reaction was also established by comparing its complex with structural features of the analogous Co(II) complex, the latter revealing no ring closure to give benzothiazole substituents and co-crystallisation of a mixed Co(II)/Co(III) complex. Finally, the structure and photophysical properties of the corresponding 3,4-diphenyl-2,5-bis(benzothiozol-5-yl)-pyrrole ligand, obtained via treatment of the thioamide with K(3)[Fe(CN)(6)], were also investigated revealing a blue-centered emission.     

基于新型硅基化合物衍生物的有机电致发光器件

利用真空蒸镀方法, 以两种新型硅基化合物同族衍生物材料BMPSiE(1,2-bis(1-methyl-2,3,4,5-tetraphenyl-1H-Silole-1-yl)ethane)和BMPThSi(1,1’-dimethyl-3,3’,4,4’-tetraphenyl-2,2’,5,5’-tetra(thiophen-2-yl)-1,1’-bi(1 H-silole))为发光层, NPB(N,N’-diphenyl-N,N’-bis (3-methylphenyl)-1,1’-biphenyl-4,4’-diamine)和Alq3(tris (8-hydroxyquinolinolato) aluminum)分别为空穴和电子传输层, 制备了结构简单的高亮度电致发光器件, 表征了器件的光电性能, 并通过器件的能级结构对器件的发光机理进行了讨论. 结果表明, 驱动电压为20 V时, BMPSiE和BMPThSi的三层结构的器件最大亮度分别为9991.9 和15261.5 cd·m-2, 流明效率分别为0.36 和0.31 lm·W-1. 器件发光光谱谱峰位于483和495 nm处, 分别为BMPSiE和BMPThSi的特征光谱, CIE(国际发光照明委员会)色度图坐标为(0.202, 0.337)和(0.246, 0.419),且不随外加电压的改变而变化.     

Miscibility of Halogen-containing Polymethacrylates with Various Poly(alkyl acrylate)s

The miscibility behavior of a series of halogen-containing polymethacrylates with poly(methyl acrylate), poly(ethyl acrylate), poly(n-propyl acrylate) and poly(n-butyl acrylate) was investigated by differential scanning calorimetry and for lower critical solution temperature (LCST) behavior. Poly(chloromethyl methacrylate), poly(1-chloroethyl methacrylate), poly(2-chloroethyl methacrylate), poly(2,2-dichloroethyl methacrylate), poly(2,2,2-trichloroethyl methacrylate), poly(2-fluoroethyl methacrylate) and poly(1,3-difluoroisopropyl methacrylate) are miscible with some of the poly(alkyl acrylate)s. Most of the miscible blends show LCST behavior. However, poly(3-choloropropyl methacrylate), poly(3-fluoropropyl methacrylate), poly(4-fluorobutyl methacrylate), poly(1,1,1,3,3,3-hexafluoroisopropyl methacrylate), poly(2-bromoethyl methacrylate) and poly(2-iodoethyl methacrylate) are immiscible with any of the poly(alkyl acrylate)s studied. © 1997 John Wiley & Sons, Ltd.     

Cycloaddition of dialkylgermoles: synthesis and structures of 2,2,3,3-tetracyano-1,4,5,6-tetraphenyl-7-germanorborn-5-enes

Cycloaddition reactions of 1,1-dicyclopropyl-2,3,4,5-tetraphenyl-1-germacyclopentadiene (3) with dehydrobenzene, tetracyanoethylene, cyclooctyne, or dimethyl acetylenedicarboxylate as well as of 1,1-dimethy-2,3,4,5-tetraphenyl-1-germacyclopentadiene (4) and 2,3,4,5-tetraphenyl-1-germacyclopentadiene (5) with tetracyanoethylene or cyclooctyne were studied. Diels—Alder adducts of germoles3, 4, and5 with tetracyanoethylene were prepared. The structures of these adducts were established by X-ray diffraction analysis and their thermal and photochemical stabilities were examined. Published inIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 7, pp. 1278–1284, July, 2000.     

Pyrylium salts in the synthesis of redoxites

Redoxites poly(2,6-diphenyl-4-vinylpyran), poly(2,6-diphenyl-4-vinylpyrylium perchlorate), poly-(2,6-diphenyl-4-vinylpyridine) and poly(2,2′,6,6′-tetraphenyl-γ,γ′-dipyridine) were obtained based on pyrylium salts. Poly(2,2′,6,6′-tetraphenyl-γ,γ′-dipyridine) was transformed into the polyene to improve its film-forming and conducting properties. Electrochemical properties of polyviologen and conductive properties of the obtained polymers were studied.     

Unexpected synthesis of a naphthylsilole

The reaction of 1,4-dilithiotetraphenylbutadiene (2) with 1,1′-dichloro-2,3,4,5-tetraphenyl-1-silole (3) leads to 2,3,4,5-tetraphenyl-1-(1,2,3-triphenylnaphthalen-4-yl)-1H-silole (5) instead of the expected octaphenyl-1,1′-spirobisilole (1). The reaction of 2 with SiC1₄ in dioxane produced 1 in low yield, confirming results reported earlier.     

Radiolysis of polymers of chlorine methacrylates

Polymers of α-chloroacrylate (MCA), 1-chloroethyl methacrylate (1CEMA), 2-chloroethyl methacrylate (2CEMA), 2,2,2-trichloroethyl methacrylate (trCEMA) and 1,2,2,2-tetrachloroethyl methacrylate (teCEMA) were γ-irradiated at 77 K. The primary radicals were generated by the abstraction of chlorine. They decay or change into chain end radicals upon warming up to room temperature.     

Synthesis and study on 2,4,6,8-tetraaryl- 3,7-diazabicyclo[3.3.1]nonanes and their derivatives

1-Carbethoxy-2,4,6,8-tetraaryl-3,7-diazabicyclo[3.3.1] nonan-9-ones (1, 2) were synthesized and their 1H and 13C NMR data are reported. Chemical shifts and spectral assignments for 2,4,6,8-tetrakis(4-chlorophenyl)-3,7-diazabicyclo[3.3.1]nonan-9-one (3), 2,4,6,8-tetraphenyl-3-thia-7-azabicyclo[3.3.1]nonan-9-one (4) and 2,4,6,8-tetraaryl-3,7-diazabicyclo[3.3.1]nonanes (5-7) are also included.