ORGANIC POLAROGRAPHY. STANLEY WAWZONEK, State University of Iowa, Iowa City, Iowa
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substituted napthoquinones (105), CY-tocopheryl quinone (115). anthraquinones (3,$,45),and toluquinones related to mold metabolites (85). In the last example no definite relationship was found between the half-wave potentials and the antibacterial activity. The polarographic method has been used to folloiv the effect of ultraviolet light on quinones (91). Methylene quinone systems which occur in citrinin (I) (55,85), fuchsones (11) (119), and the colored forms of phenolphthalein (111) (68) and fluorescein (%), are irreversible even though they rescmble quinones in structure. Thus, introduction of substituents into fuchsone produces no shift in half-wave potential. This behavior parallels that observed with benzophenone rather than with benzoquinone (119).
HE past 8 years have saen considerable advancement in the field of organic polarography. Developments were of three types: reinterpretation of previous work; investigation of the oxidation and reduction of new types of organic compounds; and applications of the polarographic method t o quantitative estimation, structure, determination, and preparation of organic compounds. The polarographic investigations in most cases have been carried out more carefullv and more completely than in the past and the half-wave potential has been accepted as a standard measurement The interpretation of the nature of the reduction and of the Eduction products in irreversible systems leaves much to be desired. There is a tendency to base the interpretations solely on the number of electrons involved in the reduction with no regard for organic chemistry. Often well known compounds Tvhich might react further, are postulated as end products without being studied polarographically. The majority of the work has been carried out in mixtures of water and organic solvents. I n nonaqueous media such as acetic acid ( 5 ) ,formaniide, ethyl alcohol, methyl alcohol, glycerol (102), and ethylene glycol (46),the waves are lower and in some cases more d r a m out than those obtained for the same concentration i n water.
