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Complexes cis‐[Pd(ArF)2(NCMe)2] (A) and cis‐[Pd(ArF)2(THF)2] (B) (ArF=C6F3H2) are fast general precursors easy to prepare, store and handle, which allow in situ synthesis of tailor‐made [Pd(Ar)(X)(L)] catalysts for chosen Ar‐Nu couplings, provided that the L ligand (in this case PR2(2‐biaryl)) induces (ArF)2 coupling. This fluorinated byproduct is inert in the reaction conditions, and no other byproduct is expected because the Ar and X groups are the same in the catalyst, the intermediates and the products. The application of A or B in catalysis (e. g. with 1% catalyst) consists of a first step (formation of 1% tailor‐made catalyst) where 100 ArX+1 A (or B)+1 L in THF gives a solution with 99 ArX+1 [Pd(Ar)(X)(L)]+(ArF)2. The only other byproduct is THF or NCMe. In the second step, addition of the nucleophile, 100 Q(Nu), triggers and completes the catalytic cycle yielding 100 Ar‐Nu+100 Q(X)+1 [Pd0(L)]. The 100% yield is theoretical, but the tested catalysis (Ar‐Me Negishi coupling, C6F5‐alkynyl Stille coupling and Ar‐naphthyl Suzuki coupling) using A as precursor, SPhos as ligand, and 1000:1 reagents:catalyst ratio, afford 95–99% yield. In contrast, aryl‐amination requires 1000:5 ratio to give 96% yield (or 1000:50 for 99% yield) because PhNH2 eventually displaces the SPhos from Pd and blocks the catalyst. As a bonus, the presence of F in the precursors facilitates stepwise 19F NMR monitoring of the formation of [Pd(Ar)(X)(L)] with different phosphines, facilitating analysis of weaknesses or strengths of each of them to produce the catalyst, and helps in the choice of the most convenient one for the case. The in situ catalyst formation is ideal for serial two‐step catalysis with different phosphines or different nucleophiles. [ABSTRACT FROM AUTHOR]

Complexes trans-[PdX2L2] (X = Cl and Br), where L is 1-(PR2),2-(CH＝CH–C(O)Ph)-C6F4 (R = Ph, Cy, and iPr), display phosphorescent emission in the solid state, whereas due to their substantially lower lifetimes, the free ligands exhibit fluorescent behaviour. Alternatively, structurally identical derivatives with halide replaced by CN− or Pd replaced by Pt are non-emissive. DFT calculations explain this diverse behaviour, showing that the hybridization of orbitals of the MX2 moiety with those of the chalcone fragment of ligands is significant only for the LUMO of the emissive compounds. In other words, in our complexes, only MLMCT processes (LM = Metal-perturbed Ligand-centered orbital) lead to observable luminescence. [ABSTRACT FROM AUTHOR]

RhI complexes [Rh(L)4](A) (A− = Cl−, BF4−, [Au(CN)2]−) with conventional arylisocyanides (p-MeC6H4(NC), LA; p-MeOC6H4(NC), LB; 3,5-(OMe)2C6H3(NC), LC) or with the alkoxy-functionalized triphenylene-arylisocyanides TPh(OC12H25)5(O(CH2)6OC6H4(NC)-p) (LD1) and TPh(OC12H25)5(O(CH2)6OC6H2Me2(NC)-p) (LD2), have been prepared and their self-assembly, aggregation, optical, redox, mesogenic and conducting properties investigated. Intermolecular π–π stacking, RhI⋯RhI, and RhI⋯AuI interactions rule the crystal packing and aggregation in solution for the complexes with LA, LB, and LC. For the RhI complexes with the alkoxy-functionalized-triphenylene isocyanides LD1 and LD2 mesogenic behaviour is induced, giving rise to multicolumnar mesophases in broad temperature ranges (ca. 70–160 °C). Detailed analysis (POM, DSC, SAXS/WAXS and GIWAXS) of the columnar mesophases has allowed us to propose precise packing models that explain the diverse supramolecular arrangements found in the nanostructured condensed phases. Columnar alignments predominantly with Rh⋯Rh interactions (or Rh⋯Au, only for LD2 in specific conditions) are observed, depending on the aligning conditions. The hole mobility in the columnar mesophases of the complexes with Rh⋯Rh interactions are ∼1 cm2 V−1 s−1, that is up to four orders of magnitude higher than those reported for columnar mesophases of organic triphenylene derivatives, and increases one order of magnitude further in the mesophases containing the [Au(CN)2]− counteranion. [ABSTRACT FROM AUTHOR]

A new system based on dinuclear gold complexes with biphenyl isocyanides which shows luminescence properties and also liquid crystal behavior is reported. All the gold(I) derivatives except the phenylisonitrilegold(I) derivative [[mu]-(1,4-CN-[C.sub.6][H.sub.4]-NC)[{Au([C.sub.6][F.sub.4]O[C.sub.6][H.sub.17]}.sub.2] display liquid crystal behavior giving rise to a nematic mesophase.

Research has been conducted on binuclear mesogenic copper(I) isocyanide complexes with a tetrahedral core. The preparation of these complexes and the relationship between the thermal behavior of these complexes and their molecular structure are described.

The platinum amides exhibit planar arylamido moieties and hindered rotation around the N-aryl and Pt-N bonds. Data indicate that the rotation about the Pt-N bond is unfavorable due to steric congestion with the planar amide.

Research has been conducted on the rhodium(I) complexes. The synthesis and structures of these complexes with the ligands PePy (sub)n are discussed.

The process of interconversion of the syn and anti-rotational isomers of cis-(Pd(2-C6BrF4)2(tht)2)(tht = tetrahydrothiophene) was studied by 19F NMR magnetization transfer experiments. The first-order syn-to-anti atropisomerization rate constant k(sub ab) decreased with the addition of tht until it reached an asymptotic value (1.414 + O.012s-1 at 299.1 K). This behavior revealed a dual mechanism involving two competitive pathways.

The chemical process involving palladium-catalyzed cross-coupling of organotin reagents with organic electrophiles (Stille reaction) has become a favored technique in contemporary organic synthesis primarily because of the benefits of using trialkylorganotin species. The Still reaction technique is critically evaluated with regard to certain inconsistencies and a plausible correction mechanism is proposed.

Four complexes of [Pd(C6F5)2(SPPynPh3-n)] are synthesized. Three of the complexes exhibit slow equilibrium of the N,N- and N,S- isomers. Intramolecular substitution process in two N,S- isomers is found to take place by a turnstyle mechanism in a square-pyramidal intermediate. This mechanism is favored over the more common Berry pseudorotation in a trigonal-bipyramidal intermediate.

The ligands P(CH2CH2Py)Ph2 (PN), P(CH2-CH2Py)2Ph (PN2) and P(CH2CH2Py)3 (PN3) act as bidentate P,N-chelating ligands in a number of neutral palladium(II) complexes of the type [PdRCl(PNn)] prepared with these ligands. For neutral complexes, the base-catalyzed addition of P-H bonds to 2-vinylpyridine offers an easy way to prepare (2-pyridylethyl)phosphines PNn. These react with dimers [Pd2-(mu-Cl)2(R)2(tht)2] to generate the neutral complexes [PdCl(R)(PNn0)]. For cationic complexes, the position previously occupied by the halide must be filled by the second Py group.