Treatment of cis-(dfmp)2PtMe2 (dfmp = (C2F5)2PMe) with the mesitylenium acid (C6Me3H4)+B­(C6F5)4 – in 1,2-difluorobenzene cleanly produces an unusually stable arene complex, [(η6-C6Me3H3)­Pt­(dfmp)­(CH3)]+(B­(C6F5)4)− (1). Facile arene exchange and competitive binding equilibria have been quantified for mesitylene relative to toluene (K = 0.0030(3)) and durene (K = 20(2)). Reaction of 1 with H2 at 80 °C results in hydrogenolysis to form the arene hydride (η6-C6Me3H3)­Pt­(dfmp)­(H)+ (2), while treatment of 1 with CO gives trans-(dfmp)2Pt­(CO)­Me+ as the major phosphine product. Addition of excess Me3P to 1 results in both arene and dfmp displacement to form (Me3P)3PtMe+. (η6-C6Me3H3)­Pt­(dfmp)­(CH3)+ is a moderately active ethylene dimerization catalyst to form 2-butenes (∼7 TO h–1, 20 °C).

The synthesis and structural characterization of 2-and 3-coordinate Pt(0) complexes with -acceptor perfluoroalkylphosphine ligands (PFAP's) is reported. (dfebp) 2 Pt (dfebp = (C 2 F 5) 2 P t Bu) was prepared in moderate yield by either thermolysis of (cod)Pt(Ph) 2 in neat dfebp or, more efficiently, by the treatment of (nbe) 3 Pt with 2 equiv. dfebp in the presence of H 2. Addition of 1 equiv. CF 3 CO 2 H to (dfebp) 2 Pt generates the expected Pt(II) trans-(dfebp) 2 Pt(O 2 CCF 3)(H) product, while treatment with the mesitylenium acid (C 6 Me 3 H 4) + B(C 6 F 5) 4 leads to phosphine loss and formation of the arene complex [( 6-C 6 Me 3 H 3)Pt(dfmp)(CH 3)] + (B(C 6 F 5) 4)-. Addition of ethylene to (dfebp) 2 Pt results in facile and reversible equilibria with the ethylene adducts (dfebp) 2 Pt(C 2 H 4) and (dfebp)Pt(C 2 H 4) 2 , which have been quantified by VT NMR spectroscopy.