Spectrophotometric determination of H(2)O(2) with 1-anilinonaphthalene-8-sulfonic acid and 4-aminoantipyrine with hematin as catalyst

A spectrophotometric flow injection method for the determination of H(2)O(2) in aqueous solution is presented. The technique is based on the oxidative condensation reaction between 1-anilinonaphthalene-8-sulfonic acid (ANSA) and 4-aminoantipyrine (AAP) in the presence of H(2)O(2). Hematin is a good peroxidatic catalyst for this reaction; its effectiveness is significantly enhanced in an ammoniacal medium. If the yellow product formed in the alkaline medium is acidified, a blue chromophore (lambda(max) 592 nm) is formed; a surfactant is necessary to keep the blue compound in solution. Chemical and instrumental parameters for FIA were evaluated and optimized. A detection limit of 0.3muM was achieved with a linear dynamic range extending to 50muM. The typical relative standard deviation is 1.5% or better. The structure of the reaction product has been identified.     

A polystyrene-supported triflating reagent for the synthesis of aryl triflates

An insoluble polystyrene-supported triflating reagent has been prepared by suspension co-polymerization of N-(4-vinylphenyl)trifluoromethanesulphonimide, styrene and the JandaJel^® cross-linker. This reagent, in the presence of triethylamine, allows for the efficient synthesis of aryl triflates from a wide range of phenols in a process that permits the desired product to be isolated from the reaction mixture in essentially pure form via several filtration and concentration operations. Adding to the utility of this reagent is its ability to be easily recovered, regenerated and reused. Both soluble and insoluble bifunctional polymers containing trialkylamine moieties in addition to triflimide groups were also prepared and examined as triflating reagents. Unfortunately these reagents afforded only modest yields of the desired products in representative reactions.