Multinuclear 195 Pt and 15 N magnetic resonance spectroscopic studies of the reaction of K[PtCl 3 (NH 3 )] with KI and amines

Reaction of the platinum complex K[PtCl 3 (NH 3 )] with NH 3 or NH 2 (CH 2 ) n NH 2 in the presence of I − gives the mixed chloroiodoamine complexes cis ‐[PtCl 3 (NH 3 ) 2 ] and [{ cis ‐Pt(Cl) 3 (I)(NH 3 ) 2 } 2 μNH 2 (CH 2 ) n NH 2 ], respectively. These findings prompted an examination of the nature of the reaction of K[PtCl 3 (NH 3 )] with I − in detail. Rapid displacement of two chlorides to give the trans ‐[Pt(I) 2 Cl(NH 3 )] − anion is observed with a subsequent slow displacement of the third chloride to give the [PtI 3 (NH 3 )] − anion. Concomitant with the formation of the triiodo anion, dimerization occurs, giving the iodo‐bridged compound [PtI 2 (NH 3 )] 2 . Correlation of δ( 195 Pt) and δ( 15 N) chemical shifts and 1 J ( 195 Pt, 15 N) coupling constants was made with literature values, allowing a complete set of data for the series [PtX n (NH 3 ) 4 − n ] (2 − n)+ with systematic variation of X (Cl,I) to be presented.