Compounds of Platinum in Lower Oxidation States. II. Evidence for the

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GEORGE1%'. ~

~ A AND T T JANES

11. D.1U'ES

1C O N T R I R U T I O Y FROM THE DEPARTMENT O F CHEMISTRY,

THEITSIVERSITY

1-01. $1 OF TEXAS]

Compounds of Platinum in Lower Oxidation States. 11. Evidence for the Existence of K[Pt(en-H)(en-ZH) and [Pt(en)(en-H)]' BY GEORGEW. WATT AND JAMES W. DAWES RECEIVED JULY 2, 1968 The reaction of bisethylenediaIllineplatinuiii( 11) iodide in liquid ammonia a t -33.8' witn potassium amide in excess of three molar equivalents has been shown most probably to yield ammonia-soluble K[Ptr1(en-H)(en-2Hj]. T h e reaction of the iodide with successive one molar equivalent quantities of potassium amide and potassium has provided indirect evidence for the formation of unstable [Ptr(en)(en-H)]O;the role of this species in the spontaneous decomposition of [Pt(en),]o is discussed.

I t was reported2 previously that bisethylenediExperimental amineplatinum(I1) iodide reacts with one and two All materials, experimental methods and procedures equivalents of potassium amide in liquid ammonia to employed in this work were essentially the same as those provide basic platinum-ethylenediamine complexes described or referred to previously.* The Conversion of [Pt(en-Hjs] to K[Pt(en-Hj(en-PH)] .in which one and two protons, respectively, are re- Since all of the ultimate Droducts of the direct treatment of moved from the amino groups of the coordinated bisethylenediamineplatin;m(II) iodide with excess potasligands. The reduction of bisethylenediamineplat- sium amide are ammonia-soluble, the complexity of the end inum(I1) iodide was shown to yield compounds of product mixture was minimized as follows. A 3.2345-g. in 76 ml. of anhydrous liquid ammonia sample of [Pt(en)~]In Pt