| The synthesis and reactivity of new perfluoroalkylphosphine complexes of platinum has been investigated. Following up on previous protonolysis studies of (dfepe)Pt(Me)(X) (dfepe = (C2F5)2PCH 2CH2P(C2F5)2; X = O 2CCF3, OTf, OSO2F) we have explored the effects of varying both the hybridization and substituents on the methyl carbon. Despite prior extensive kinetic studies, we were previously unable to determine the pathway by which these protonolyses proceed. We report the synthesis and protolytic stability of (dfepe)Pt(Ph)X and, by using the Puddephatt criterion, have determined that protonolysis most likely occurs via the SE2 mechanism in our systems.;Aliphatic Pt(II)-carbene complexes have never been identified and thus pose intriguing synthetic challenges. By taking advantage of the stability of (dfepe)Pt-C bonds, sigma-alkenyl precursors can be made. These complexes may possibly allow for the generation of carbenium ion centers ("metallocarbenium" ions) by isomerization. Likewise, routes to heteroatom-modified alkyl (M-RX) precursors would allow for the generation of carbenium ion centers by loss/abstraction of the X group. A series of (dfepe)Pt(eta2-RC ≡ CR ') complexes (R = Me, R' = H; R = tert-butyl, R' = H; R = Me3Si, R ' = Me; R = Ph, R' = Me; R = R' = Me; R = R' = Ph) have been prepared in order to examine the addition of Bronsted acids to form alkenyl complexes (dfepe)Pt(C(R ') = C(H)R)(X). The synthesis of (dfepe)Pt(CH2Cl)(OTf) and chloride abstraction using SbF5 are also reported along with preliminary reactivity studies. |
