Polarography of some coordination compounds of Platinum. III. Ions of the tetrammineplatinum(II) type
JR Hall and RA Plowman
Australian Journal of Chemistry
9(1) 14 - 24
Published: 1956
Abstract
A number of tetrammine ions of divalent platinum, in which the ligands were ammonia, methylamine, dimethylamine, ethylenediamine, pyridine, aniline, and combinations of some of these, were studied at the dropping mercury electrode. Some of the ions showed maxima in their current-voltage curves (c-v curves). The formation of hydrogen interfered with the c-v curves of other ions, so that limiting currents were not obtainable. A method was devised for the measurement of a voltage by means of which the ease of reduction of the ions could be compared. Using a supporting electrolyte of 0.1M KCl and 0.01% gelatin, the order of increasing ease of reduction was found to be [Pt{(CH3)2NH)4]2+ = [Pt(NH3)4]2+ = [Pt(NH3)3(C5H5N)]2+ = [Pt{C2H4(NH2)2}2]2+ < cis-[Pt(NH3)2(C5H5N)2]2+ < trans-[Pt(NH3)2C5H5N)2]2+ < [Pt(CH3NH2)4]2+ = [Pt(NH3)(C5H5N)3]2+ <[Pt(C6H5N)4]2+ < cis-[Pt(NH3)2(C6H5NH2)2]2+ < trans-[Pt(NH3)2(C6H5NH2)2]2+. When the ammonia groups of [Pt(NHS),l2+ were successively replaced by pyridine groups, the resulting e-v curves shifted progressively to more positive voltages. It was also found that cis- and trans-isomers of [PtA,B,I2+ reduced at different voltages. The trans-isomer reduced more readily.https://doi.org/10.1071/CH9560014
© CSIRO 1956
