Synthesis and structure of alkynylplatinum(IV) complexes containing the pincer group [2,6-(dimethylaminomethyl)phenyl-N, C, N]−

Reaction of phenyl(trimethylsilylalkynyl)iodine(III) triflate with PtII(O2CAr)(NCN) (Ar = Ph, 4-trifluoromethylphenyl (ArF); NCN = [C6H3(CH2NMe2)2-2,6]) at ambient temperature gives solutions of PtIV(O2CAr)(OTf)(Ctriple bond; length of mdashCSiMe3)(NCN) [Ar = Ph (1a); Ar = ArF (1b)]. Addition of sodium iodide (NaI) to 1 results in the isolation of PtIV(O2CAr)I(Ctriple bond; length of mdashCSiMe3)(NCN) [Ar = Ph (2a); Ar = ArF (2b)] in >90% yields. In these first examples of alkynyl(pincer)platinum(IV) complexes, the pincer group is present as a mer-[NCN]− tridentate donor and the alkynyl group is located cis to the pincer carbon donor, and the triflate (1a, 1b) and iodide groups (2a, 2b) are located trans to the pincer carbon; an X-ray structural analysis has been completed for 2b.