19900-52-8Relevant articles and documents
New cyanopyridine based conjugative polymers as blue emitters: Synthesis, photophysical, theoretical and electroluminescence studies
Pilicode, Naveenchandra,K M, Nimith,M N, Satyanarayan,Adhikari, Airody Vasudeva
, p. 6 - 15 (2018/06/19)
Herein, we report the design of three new blue light emitting conjugated polymers (Th-Py-1, Th-Py-2 and Th-Py-3), carrying cyanopyridine ring as a strong electron accepting unit and thiophene as well as phenylene vinylene scaffolds with different substituents, as electron donating moieties. The newly designed monomers/polymers were synthesized using well-known synthetic protocols such as cyclocondensation, O-alkylation, Suzuki cross coupling, Wittig and Knoevenagel reactions. They were well-characterized by spectral, thermal, photophysical, electrochemical and gel permeation chromatography (GPC) techniques. Further, they were subjected to theoretical studies using DFT simulations, performed at B3LYP/TZVP level using Turbomole 7.2 V software package. The new polymers were tested in PLED devices (ITO/PEDOT: PSS/Polymer/Al) as emissive materials. Optical studies revealed that, all the polymers displayed light absorption in the range of 377–397 nm and blue light emission in the order of 432–482 nm, respectively. Further, their band-gaps were calculated to be in the order of 2.55–2.64 eV using both optical and electrochemical data. Furthermore, the TGA study indicated that, they possess good thermal stability with onset decomposition temperature, greater than 300 ?C under nitrogen atmosphere. Interestingly, use of these polymers in new PLEDs as emissive layers, has shown improved performance when compared to previously reported polymers in similar type of devices. They show blue light emission with a low threshold voltage of 3.5–3.9 V, affirming an efficient electron injection in the diodes.
X-Ray structure determinations of bromo and/or bromomethylsubstituted benzenes: C-H···Br, C-Br···Br, and C-Br···p interactions
Jones, Peter G.,Kus, Piotr,Dix, Ina
, p. 1273 - 1281 (2013/02/23)
The structures of seven benzene derivatives [1,2,3-tri(bromomethyl)benzene, (1); 3,5-di(bromomethyl)bromobenzene, (2); 2,5-di(bromomethyl)bromobenzene, (3); 4-(bromomethyl)-2,5-dibromotoluene, (4); 4-(bromomethyl)bromobenzene, (5); 2,3-di(bromomethyl)bromobenzene, (6) and (bromomethyl)-p-dibromobenzene, (7)] with bromo and bromomethyl (and in one case methyl) substituents are presented and analysed in terms of Br···Br interactions up to 4.0 A , supported by hydrogen bonds H···Br. Some interactions of the type Br···π and π·· · π are encountered and play a subordinate role in the packing. Despite the close chemical similarity of the compounds, some of which are isomers with permuted substituent positions, the packing motifs are highly variable. Compounds 2-5 are based on layer structures with Brn (n=3, 4) and/or mixed Br/C rings. Compounds 1, 6 and 7 display three-dimensional packings of differing complexity, but with interpretable substructures; 1 can be analysed in terms of ribbons of linked Br3 and Br4 rings; 6 displays chains of linked Br3 triangles; 7 consists of ribbons of linked Br4 quadrilaterals.
Preparation and spectroscopic study of 13-substituted 2,11- dithiahexahydro[3.3]paracyclophanes
Lin, Shaw-Tao,Yang, Ya-Chen,Lin, Shu-Farn,Hwang, Lih-Jiun
, p. 708 - 711 (2007/10/03)
A series of 13-substituted 2,11-dithiahexahydro[3.3]paracyclophanes each containing a substituent on the benzene ring were prepared for 1H NMR and X-ray diffraction analyses. The benzene ring and the cyclohexane ring demonstrate shielding of th
