O-Phenanthroline CAS# 66-71-7

Part 2: In-depth development

A common ligand for the spectroscopic determination of metals and the spectroscopic analysis of CO2 reduction. Used in Cu(II)-catalyzed cross-linking reactions of organoboron acids, etc. Also used as a redox indicator and as a reagent for the determination of ferrous titania. Forms complexes with iron, copper, cobalt, nickel, and 2,2′-bipyridine, and red complexes with Fe2+, which are oxidized with potassium permanganate to give 2,2′-dipyridyl-3,3′-dicarboxylic acid. It can be used as a quantitative colorimetric reagent for copper and iron, and as an indicator for the titration of iron salts with cerium sulfate; it can also be used as a dye for animal fibers. The o-phenanthroline-Fe(II) indicator can be prepared by dissolving 1.485 g of the o-phenanthroline monohydrate and 0.695 g of FeSO4?7H2O in 100 mL of water. Indicator for the titration of iron salts with sulfur acid high cerium. A related ligand is a red phenanthroline (BPT), 4,7-diphenyl-1,10-o-phenanthroline. O-phenanthroline can also be used for the analysis of the content of lithium alkyl compounds. The procedure is to allow the sample to interact with a small amount (approximately 1 mg) of o-phenanthroline, which takes on a dark color, and then titrate with alcohol until a colorless titration endpoint is reached. In solutions of pH=2~9, o-phenanthroline reacts chromogenically with 2-valent ferrous ions (Fe2+). The reaction is highly selective and the resulting orange-red complex is very stable, lgK stable=21.3 (20°C) and its solution has a maximum absorption peak at 510nm (visible light). Using this color development reaction, trace amounts of iron can be determined by visible light spectrophotometry.