Recent Polarographic Studies on the Carbonyl Compounds (Part 2) Aromatic Compounds.

Abstract

Developments in polarography of carbonyl compounds on and after 1950 has been reviewed. The aliphatic and aromatic carbonyl compounds were described in Parts 1 and 2, respectively. Part 1 (This review, 6, 124 (1958)) The kinetic current of formaldehyde in buffered and unbuffered solution of alkaline pH were discussed, and the half wave potentials of some saturated aldehydes and chlorinated aldehydes were listed in tables. Possible reduction process of glyoxal were formulated under consideration of the kinetic current which was similar to that of formaldehyde. The kinetic current of a-d-glucose, mutarotation of which was contained in the reaction process, was discussed. Equations which expressed the relationship between the half-wave potentials of polyenealdehydes at pH 0 and the number of double bonds were shown, and the calculated and observed half wave potentials were tabulated. The half-wave potentials of terpenealdehydes and ketones were listed in Tables 6 and 11, respectively. The recombination rate constant of pyruvate ion with proton was given by the theoretical equation, and the rate constants of some derivatives of pyruvic acid were tabulated. Reducibility of chaine and cyclic diketones were explained from view point of the stcric hindrance. The polarographic behaviors of several oxocamphors were summarized in Table 10. The kinetic current of dehydroascorbic acid and reversibility of ascorbic acid-dehydroascorbic acid system were discussed. The half-wave potentials of pyrethroid compounds were given in Table 12 and the polarographic behaviors of various keto-steroids were described. Part 2. The general behavior of the aromatic carbonyl compounds was described and the possible reduction mechanism in the alkaline medium was discussed. The half-wave potentials of substituted benzaldehydes were listed in Table 13, and the influence of the substituents on the reduction process of several compounds was discussed. The half wave potentials of saturated mono-ketones and these derivatives were summarized in Tables 15-18. Possible reduction mechanism of benzil, ninhydrine, which gives some reduction waves with the kinetic character, and some unsaturated ketones were postulated. The kinetic current of phenylglyoxylic acid and the chemical kinetics of phenylglyoxal in alkaline medium were discussed. The polarographic behavior and the reduction process of trooone and topolone derivatives were described, and that of flavone, isoflavone and formyl pyridine in hetero-cyclic compounds were reviewed.