The reaction of hexachloroplatinic acid with aromatic compounds affording the σ-aryl complexes of platinum(IV)

Cyclometallated platinum(ii) complexes: oxidation to, and C–H activation by, platinum(iv)

“…19 Even though the reductive elimination of hydrocarbons from platinum(IV), which can be seen as analogous to the reverse of a C-H activation, has been widely studied, 20-25 and the Pt(II)/Pt(IV) redox cycle has been investigated as a model for the activation of C-H bonds, 26, 27 there have been few reports of C-H activation by a platinum(IV) centre to date. [28][29][30][31] Here we report the synthesis of some cyclometallated platinum(II) compounds derived from substituted phenylpyridines and discuss the reactivity of these complexes with respect to oxidation. We also report the generation of new platinum(IV) species that can only have arisen from the cyclometallation (C-H activation) of other platinum(IV) species.…”

Structure of trimethylplatinum(IV) with a tripod ligand

“…8533. 0108-2701/92/091603-04506.00 Labinger, Herring & Bercaw, 1990a,b) has led to our synthesizing model Pt complexes containing 'hard' ligands (Herring, Henling, Labinger & Bercaw, 1991). Model complexes analogous to the putative Pt(R)Cla(H20)-species that have been proposed as intermediates in the activation/functionalization of alkanes by Pt (Shul'pin, Shilov, Kitaigorodskii & Zeile Krevor, 1980;Shibaera, Rozenberg, Lobkovskaya, Shilov & Shul'pin, 1981;Shul'pin, Nizova & Nikitaev, 1984;Khrushch, Laurushki, Misharin, Moravsky & Shilov, 1983) are thus attractive targets, but few examples of structurally well characterized complexes are available. The tripod ligand (r/5-CsHs)Co[P(O)(OR)d3 (henceforth abbreviated to LoR) behaves as a hard ligand, with field strengths approximately equal to that of three F-ligands (Kl/iui, 1990).…”

Electrophilic thallation of phenol and its derivatives with phenylthallium(III) crown ether complexes

“…Determination of the Thallated Position in [Phenyl(hydroxyaryl)thallium(III)(18-crown-6)] Perchlorate (3)(4)(5). The NMR spectrum of the hydroxyaryl protons of 5 was observed as a doublet having a coupling with the thallium nucleus (Jtih = 450 Hz, 2 H).…”

“…This result suggests that the ionic character of the Tl-C bond between the thallium atom and hydroxy aryl group in 2-12 is much smaller than those of the -halogen bonds and slightly larger than that of the T1-CH3 bond. In complexes 2,3,5,6,8,10,11, and 12a, which have no substituent at the 2/-position on the aromatic ring, the «/v alues are about 450 Hz. On the other hand in complexes 4, 7, and 9 in which the 2'-position was substituted by a methyl or hydroxyl group, the JT1Hj values are about 480 Hz. We consider that the steric repulsion between the substituent at the 2,-position and 18-crown-6 as a ligand may cause the Tl-C bond to be more ionic in 4, 7, and 9.…”