Green, near-infrared electroluminescence of novel yttrium tetrazole complexes

Abstract

Four novel yttrium complexes with the molecular formula Y(Tz) n (x) 2 (SCN) 3Àn (H 2 O), n ¼ 2, 3 and x ¼ phen, bpy, were synthesized by the reactions of yttrium salt with 5-phenyl tetrazole (Tz), 1,10-phenanthroline (phen), 2,2-bipyridine (bpy) and thiocyanate ions, and were used as the emitting material in electroluminescent devices. The structures of these complexes were determined by UV-visible and FT-IR spectroscopy, 1 H NMR, CHN analysis and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The monodentate mode of the Tz complexes was investigated by FT-IR spectroscopy. The different structures of the compounds suggest the importance of the tetrazole and auxiliary ligands in the emission properties of the yttrium complexes. It was found that the Y-polypyridine complexes dressed by tetrazole antennas have highly efficient intra-energy transfer. The Y complexes exhibited broad ligand-centered electroluminescence with maximum near 550 nm, and near-IR electroluminescence at 800, 900 and 950 nm. The electroluminescence spectra of the yttrium complexes indicated a long red shift in the visible region compared to the PVK:PBD blend. The reaction details and features were described and discussed.

Synthesis of 5-substituted 1H-tetrazoles Using Natural and Reusable Natrolite Zeolite

“…The importance of tetrazole chemistry during two decades ago, especially for their main applications in coordination chemistry, medicinal chemistry and materials applications caused to be considered by a lot of organic chemist researchers [1][2][3][4][5][6][7][8][9]. Tetrazoles can be used as isosteric replacements for carboxylic acids in drug design [2].…”

CoFe2O4 Nanoparticles as a Magnetically Recoverable and Reusable Catalyst for the Synthesis of Arylaminotetrazoles and 5-aryloxytetrazoles

“…[4][5][6][7][8][9][10][11][12][13][14][15][16] However, the lack of convenient methods for the preparation of arylaminotetrazoles restricts their potential application in medicine. Generally, arylaminotetrazoles are synthesised by the condensation reaction of cyanamides with hydrazoic acid, 17 HOAc 7 and FeCl 3 -SiO 2 13 which lead to a mixture of products. Earlier methods for the synthesis of arylaminotetrazoles or 5-aryloxytetrazoles suffer from drawbacks such as the use of strong Lewis acids or expensive and toxic metals, drastic reaction conditions, low yield, long reaction times, low temperatures (-70 °C), tedious work-up procedures due to the application of homogeneous catalyst and hydrazoic acid formation.…”

Synthesis of Thiotetrazoles and Arylaminotetrazoles Using Rutile Tio2 nanoparticles as a heterogeneous and reusable catalyst

“…This has limited the largescale applications of tetrazoles in industry. Recently tetrazoles have been prepared from the reaction between thiocyanates or nitriles with NaN 3 and NH 4 Cl as a substitute for HN 3 . 1 However, combining sodium azide with ammonium chloride as an acid may yield gaseous HN 3 which is potentially toxic.…”

“…Tetrazoles are well-documented compounds of synthetic importance that have been widely used in coordination and medicinal chemistry and in the synthesis of pharmaceutically important compounds and nitrogen-containing molecules. [1][2][3][4][5][6] Tetrazoles are conventionally synthesised by the reaction of harmful hydrazoic acid or azide ions with nitriles, thiocyanates or cyanamides in the presence of homogeneous catalysts. [3][4][5][6][7][8][9][10][11] However, these procedures suffer from disadvantages such as environmentally unpleasant use of toxic reagents or stoichiometric amounts of homogeneous mediators, long reaction times, harsh reaction conditions, tedious isolation steps and low yields of the products.…”