Palladium(II) and platinum(II)-C(3)-substituted 2,2′-bipyridines

Neutral and Cationic Methyl Complexes of Platinum(II) with 6-Substituted 2,2′-Bipyridines: Synthesis, Characterisation and Reactivity with Carbon Monoxide − Molecular Structures of [PtCl(methyl)(6-ethyl-2,2′-bipyridine)] and of [Pt(methyl)(acetonitrile)(6-ethyl-2,2′-bipyridine)][BF4]

“…The X-ray structure of this complex has recently been reported. [15] Replacement of the chloride by an iodide ion has been carried out on 2a and 3a by reaction with LiI. Alternatively, these products can be obtained by reaction of the ligands HL 2 and HL 3 with trans-[PtI(Me)(SMe 2 ) 2 ].…”

“Rollover” cyclometalation – early history, recent developments, mechanistic insights and application aspects

“…Surprisingly, in several instances, quite weakly polar solvents, like benzene, toluene, or dichloromethane, have been used for the generation of ''rollover'' cyclometalated bipy complexes. 101,107,108,[110][111][112][113][114]185 Nevertheless, at least traces of a stabilizing agent seem to be mandatory for the reactions to proceed. Although [Pt(bipy À H)(CH 3 )(DMSO)] (16) (34) undergoes ''rollover'' cyclometalation upon heating in the presence of donor ligands such as dimethyl sulfide (see Fig.…”

“…179 Hence, a consistent interpretation of the reported H/Dexchange experiments does not seem possible for the time being. 101,107,108,110,112,114,185,192,193 Platinum(II)-hydride complexes can be generated via treatment of the corresponding chlorides with NaBH 4 , 109,185,193 while the chloride analogues are generated either directly by using an appropriate chloride containing precursor, 101,109 via ligand exchange with LiCl, 101,102 or by treatment of the methyl complexes with hydrochloric acid (accompanied by some coordinative rearrangements). 107,110,112,185,192,193 However, reaction with HCl can also cause decyclometalation, 109,192 and in some cases, even new types of ''rollover'' cyclometalated complexes are accessible by this method:…”

Step by step palladium mediated syntheses of new 2-(pyridin-2-yl)-6-R-nicotinic acids and esters

“…We have previously reported on the reaction of palladium(II) acetate with two 6-alkyl-substituted-2,2 0 -bipyridines (HL 1 = 6-iso-propyl-2,2 0 -bipy; HL 2 = 6-neo-pentyl-2,2 0 -bipy) [6]. In benzene at reflux the reaction gives a crude product which, after treatment with LiCl and recrystallization, allowed us to isolate the cyclometallates [Pd(L 1 )Cl] 2 , 1, and [Pd(L 2 )Cl] 2 , 2, in low or moderate yields, respectively.…”

“…One of the most important applications is the carbonylation reaction: insertion of CO into the Pd-C bond has been particularly investigated in the case of the cyclometallates with nitrogen ligands. The stoichiometric acylation allows to synthesize heterocyclic ketones and a variety of other carbonyl compounds.We have previously reported on the reaction of palladium(II) acetate with two 6-alkyl-substituted-2,2 0 -bipyridines (HL 1 = 6-iso-propyl-2,2 0 -bipy; HL 2 = 6-neo-pentyl-2,2 0 -bipy) [6]. In benzene at reflux the reaction gives a crude product which, after treatment with LiCl and recrystallization, allowed us to isolate the cyclometallates [Pd(L 1 )Cl] 2 , 1, and [Pd(L 2 )Cl] 2 , 2, in low or moderate yields, respectively.…”