Synthesis and Spectral Characterization of Praseodymium(III) Complex with New Amino Acid-Based Azo Dye

A new Praseodymium (Pr) (III) complex has been synthesized and characterized by using a new amino acid-based (leucine) azo dye such as N,N-dimethylazoleucine (L1) and 1,10 phenanthroline (L2). Reaction of Pr(III) ion with L1 and L2 in 1？:？2？:？1 ratio in alcoholic medium has been carried out with general formula [Pr(L1)2(L2)(H2O)2]. Elemental analysis, comparative FT-IR, and 1HNMR spectral studies of Pr(III) complex with ligands have been shown in this paper. 1. Introduction Lanthanide complexes attract a growing interest in material science due to their optical and magnetic properties. Special interests are those in which ligands play a role of intramolecular sensitizer for lanthanide luminescence [1]. Therefore, the choice of ligand remains a crucial point, and molecules containing aromatic moieties are very often found to be good sensitizers for lanthanide ions. In the last decade, the new materials based on lanthanide complexes have been studied with particular interest for applications as highly efficient light conversion molecular devices. They can be used in wide range of processes and new technologies, such as fluorescent lighting, electroluminescence color displays, luminescent labels in bioaffinity assays, bioinorganic sensors, and high technology optics and optoelectronic applications [2–8]. Weissman in 1942 reported that lanthanide can be improved by using an intramolecular energy transfer, the antenna effect [1]. Common used ligands are β-diketonates and noncharged adducts like 1,10 phenanthroline or 2,2-bipyridine. A new azo dye has been synthesized, named, N,N-Dimethylazoleucine, composed of leucine (NH2CH(CH2CH(C2H6))COOH) as basic moiety and 1,2-dimethyl aniline (C6H5N(CH3)2) and its Pr(III) complex with 1,10 phenanthroline (heterocyclic compound) (L2) adduct to assess the possibilities of Pr(III) complexes formation and spectral changes that occur due to complexation. 2. Experimental 2.1. Chemicals and Measurements Elemental analysis was performed with Perkin Elmer 2400 (SAIF Chandigarh, Punjab University). FT-IR spectra were recorded with KBr pellets in 4000 to 400？cm？1 on Nicoletet Protese 460 Spectrograph EFT (IIT Delhi). 1H NMR spectra were recorded with DMSO-d6 medium on DPX-dix 300？MHz Bruker Avance spectrometer using TMS as an internal reference from 0 to 9？δ？ppm (IIT Delhi). Thermogravimetric analysis (TGA) was recorded with F-2nd Perkin Elmer F-second Pyrif Diamond in nitrogen atmosphere (IIT Delhi). Conductivities were measured with digital conductivity meter Model 621E (ranging from 0 to 1999？μS, with resolution 1？μS). The