Cumulated double bond systems as ligands : I. Dialkylsulfurdiimine compounds of platinum

The preparations and properties of a new series of compounds of the formula trans-PtCl₂(dialkylsulfurdiimine)L] are reported. In the case of the dimethyl-, diethyl-, diisopropyl- and dineopentyl-sulfurdiimine platinum compounds two isomers are present in solution, but only one isomer was observed for the di-t-butylsulfurdiimine derivative. ¹H and ¹³C NMR data show that the two isomers interconvert intramolecularly by two different routes. In one of the isomeric forms, unusually large low-field chemical shifts indicate the existence of non-bonded metal—alkyl interactions.