Reactivity of Diaryliodine(III) Triflates toward Palladium(II) and Platinum(II):  Reactions of C(sp²)−I Bonds to Form Arylmetal(IV) Complexes; Access to Dialkyl(aryl)metal(IV), 1,4-Benzenediyl-Bridged Platinum(IV), and Triphenylplatinum(IV) Species; and Structural Studies of Platinum(IV) Complexes

Diphenyliodine(III) triflate is able to transfer Ph + to Pd(II) and Pt(II) with cleavage of a phenyl−iodine bond and formation of metal(IV) species, leading to the first identified transfer of Ph + to Pd(II) from an aryl−halogen bond, and, for platinum, a methodology providing a facile route to dimethyl(aryl)platinum(IV) and 1,4-arenediyl-bridged Pt(IV) species and the first archetypal triarylplatinum(IV) complex. Thus, [IPh 2 ][OTf] reacts with PtMe 2 (bpy) (bpy = 2,2‘-bipyridine) at −50 °C to form iodobenzene and the Pt(IV) complex trans -Pt IV (OTf)Me 2 Ph(N∼N) ( 1b ) (Ph trans to OTf), and on addition of NaI, the species PtIMe 2 Ph(bpy) ( 2a (Ph cis to I) and 2b (Ph trans to I) in 2:1 ratio) may be isolated at −20 °C. Similarly, metalla(II)cyclopentane complexes M(C 4 H 8 )(bpy) react with [IPh 2 ][OTf] to form trans -Pt(OTf)(C 4 H 8 )Ph(bpy) ( 3b ) and a 1:1 ratio of cis - ( 4a ) and trans -Pd(OTf)(C 4 H 8 )Ph(bpy) ( 4b ); addition of halide ion gives trans -PtI(C 4 H 8 )Ph(bpy) ( 5b ) and a 1:3 ratio of cis and trans isomers for PdI(C 4 H 8 )Ph(bpy) ( 6a, 6b ) and PdCl(C 4 H 8 )Ph(bpy) ( 7a, 7b ). Complex 5b isomerizes to form a 2:1 mixture of cis -PtI(C 4 H 8 )Ph(bpy) ( 5a ) and 5b at ambient temperature in acetone. Dimethyl(2,2‘-bipyridine)palladium(II) reacts with [IPh 2 ][OTf] to form Pd(OTf)Me 2 Ph(bpy), followed by transfer of a methyl group from Pd(IV) to Pd(II), to form trimethylpalladium(IV) species. Dimethyl(2,2‘-bipyridine)platinum(II) reacts with [IPh(C 6 H 4 -4-I)][OTf], followed by addition of sodium iodide, to form a 1:1 mixture of trans -PtIMe 2 Ph(bpy) ( 2b ) and trans -PtIMe 2 (C 6 H 4 -4-I)(bpy) ( 8b ), and with [IPh(C 6 H 4 -4-IPh)][OTf] 2 to form the 1,4-arenediyl complex trans -1,4-{PtIMe 2 (bpy)} 2 C 6 H 4 ( 9b ). Diphenyl{di( tert -butyl)-2,2‘-bipyridine}platinum(II) reacts with [IPh 2 ][OTf] at 25 °C over 2 days to form the triphenylplatinum(IV) complex Pt(OTf)Ph 3 (Bu t 2 bpy) ( 10 ), and addition of iodide ion results in isolation of PtIPh 3 (Bu t 2 bpy) ( 11 ). Structural studies of trans -PtIMe 2 Ph(bpy) ( 2b ) and trans -Pt(C 4 H 8 )Ph(bpy) ( 5b ) reveal distorted octahedral geometry and the fac -PtC 3 configuration expected for all of the metal(IV) complexes. The compound [IPh(C 6 H 4 -4-I)][OTf] has two sets of cation−anion pairs with a complex array of weak interactions, and the cations have C−I−C angles close to 90°.