CUMULATED DOUBLE-BOND SYSTEMS AS LIGANDS .8. N-SULFINYLANILINE AND SULFURDIIMINE COMPLEXES OF PLATINUM(0) OF TYPE [PT(PPH3)2L] IN WHICH L IS PI-BONDED TO PT-CRYSTAL AND MOLECULAR-STRUCTURE OF [PT(PPH3)2-2,4,6-ME3C6H2-N=S=O)] - DETERMINATION OF 2J(P-31-N-15) AND 1J(PT-195-15N) BY P-31 AND PT-195 NMRN

Title full: Cumulated double bond systems as ligands. VIII. N-sulfinylaniline and sulfurdiimine complexes of platinum(O) of the type [Pt(PPh3)2L] in which L is π-bonded to Pt; crystal and molecular structure of [Pt(PPh3)2-2,4,6- Me3C6H2NSO)]; determination of 2J(13xP15N) and 1J(195Pt15N) by 31P and 195Pt NMR. A crystal and molecular structure determination of [Pt(PPh3)2(2,4,6-mesitylNSO)] shows a side-on coordination via the NS unit to Pt0, while the mesityl group is in the cis configuration with respect to SO. The same structure persists in solution, as shown by IR, UV, 1H-, 31P- and 195Pt-NMR studies on [Pt(PPh3)2(RNSO)] (R = Ph, 4-tol, 2-tol, 3,5-xylyl and 2,4,6-mesityl). In the case of [Pt(PPh3)2(Ph15NSO)], 31P- and 195Pt-NMR gave the cis and trans-couplings 2J(31PPt15N), 1J(31P195Pt) and 1J(195Pt15N). The PPh3 groups interchange their positions intramolecularly, probably via a rotation about the Pt(NS) axis. From the isotopic shifts (15N) in the vibrational spectra of both the free and coordinated PhNSO it is concluded that there is hardly any coupling between ν(SO) and ν(NS). In the light of these conclusions, the unstable [Pt(PPh3)2(RNSNR)] complexes, for which N-coordination has been tentatively proposed on the basis of the IR and UV spectra, were reinvestigated. It may now be concluded from 13P- and 195Pt-NMR that for [Pt(PPh3)2(Ph15NS15NPh)] the sulfurdiimine is also side-on coordinated via one NS bond. At elevated temperatures the complex is fluxional, and it is proposed that, in addition to a probable rotation about the Pt(NS) bond, there is also an intramolecular migration of the (PPh3)2Pt. © 1978.