INSERTION OF CO2-LIKE MOLECULES INTO THE PLATINUM NITROGEN BOND OF [PT(PPH3)2(PHNO)] - THE X-RAY STRUCTURES OF [PT(ON(PH)C(NPH)S)(PPH3)2] AND [PT(ON(PH)C(O)NPH)(PPH3)2]

The X-ray structure determination of the insertion product of [Pt(PPh3)2(PhNO)] (1) with PhN=C=S, [Pt{ON(Ph)C(NPh)S}(PPh3)2] [monoclinic, space group P21/n, with a = 17.779(7), b = 15.297(3), c = 17.951(4) Å, β = 109.49(2)°, and Z = 4; R = 0.036 for 4317 reflections with I ≥ 3σ(I)] has now confirmed the previously proposed structure for this compound. However, the X-ray structure determination of the insertion product with PhN=C=O, [Pt{ON(Ph)C(O)NPh}(PPh3)2] [orthorhombic, space group Pbca, with a = 25.303(8), b = 19.462(6), c = 17.451(5) Å, and Z = 8; R = 0.075 for 2 001 reflections with I ≥ 3σ(I)], while having confirmed that a C-N bond is formed within the co-ordination sphere of the metal, has shown that the entering molecule is bonded to platinum via nitrogen and not oxygen, as previously suggested. The difference in reactivity of PhN=C=S and PhN=C=O with complex (1) is discussed.