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Manganese‐catalyzed hydrogenation reactions have aroused widespread interest in recent years. Among the catalytic systems described, especially PNP‐ and NNP–Mn pincer catalysts have been reported for the hydrogenation of aldehydes, ketones, nitriles, aldimines and esters. Furthermore, NNP−Mn pincer compounds are efficient catalysts for the hydrogenolysis of less reactive amides, ureas, carbonates, and carbamates. Herein, the synthesis and application of specific imidazolylaminophosphine ligands and the corresponding Mn pincer complexes are described. These new catalysts have been characterized and studied by a combination of experimental and theoretical investigations, and their catalytic activities have been tested in several hydrogenation reactions with good to excellent performance. Especially, the reduction of N‐heterocycles can be performed under very mild conditions. [ABSTRACT FROM AUTHOR]

This article discusses a new class of binary adducts that are composed of two different cyclic trinuclear complexes (CTC@CTC'). These adducts have enhanced bonding strength and remain intact even in solution or the gas phase. They also exhibit remarkable RGB luminescence when exposed to electromagnetic irradiation or electric drive voltage. The research article provides more information on this topic and includes artwork by Danah M. Omary and Lorenzo Luciani. [Extracted from the article]

The comprehensive information about the synthetic method, structural features, aggregation properties, and the exceptional NLO/EO properties of the unconventional twisted [pi]-electron system electro-optic (EO) chromophore group, are analyzed. Results evidence the formation of centrosymmetric aggregates in concentrated solution and in the solid state.

Equilibrium constants ([K.sup.DM]) for reactions between acids and bases of the title compounds in C[D.sub.2][Cl.sub.2] (DM) have been determined by [sup.31]p and ¹H NMR spectroscopy at room temperature. [HP[Cy.sub.3]]B[Ph.sub.4] and [HP[Cy.sub.3]]B[F.sub.4], with p[K.sup.DM] assigned by literature convention to 9.7, have been used as the anchor compounds for the p[K.sup.DM] determinations. A continuous scale of p[K.sup.DM] values covering the range 9.7 to 5.7 is created with the acidic compounds [HP[R.sub.3]]B[Ph.sub.4]. Those acids with p[K.sup.DM] greater than 6 are stable, while those with more acidic cations HP[R.sub.3.sup.+] protonate B[Ph.sub.4.sup.-] to produce [R.sub.3]PB[Ph.sub.3] and benzene. The literature p[K.sup.THF] values reported for [HP[Bu.sub.2]Ph]B[Ph.sub.4], [HPMe[Ph.sub.2]]B[Ph.sub.4], and [HPEt[Ph.sub.2]]B[Ph.sub.4] are questionable because of this protonation reaction. NOE and PGSE ¹H NMR techniques are used to show that [HP[Cy.sub.2]Ph]B[Ph.sub.4] in DM exists as ion pairs and higher aggregates up to quadrupoles at the concentrations used in the acid-base studies. The new dihydrogen complexes [Ru([H.sub.2]) Cl[(P[Ph.sub.3]).sub.2](dach)]B[F.sub.4] (dach = (1R,2R)-(-)-diaminocyclohexane) and [Ru([H.sub.2])Cl{tme [P.sub.2][(NH).sub.2]}]B[F.sub.4] (tme[P.sub.2][(NH).sub.2] = [Ph.sub.2][C.sub.6][H.sub.4]C[H.sub.2]NHC[Me.sub.2]C[Me.sub.2] NHC[H.sub.2][C.sub.6][H.sub.4]P[Ph.sub.2]) were prepared by reaction of RuHCl[(P[Ph.sub.3]).sub.2](dach) and RuHCl{tme[P.sub.2][(NH).sub.2]} with HB[F.sub.4]. Their crystal structures are reported, and the p[K.sup.DM] values of their B[Ph.sub.4.sup.-] salts were determined to be 8.6 and 6.9, respectively. Key words: acidity, dihydrogen complex, hydride, phosphonium, dichloromethane. Operant a la temperature et dans le C[D.sub.2][Cl.sub.2] (DM) comme solvant et faisant appel a la spectroscopie RMN du ¹H et du ¹P, on a determine les constantes d'equilibre, [K.sup.DM], des reactions entres les acides et les bases des composes mentionnes dans le titre. La valeur de 9,7 attribuee par convention dans la litterature pour les composes [HP[Cy.sub.3]]B[Ph.sub.4] et [HP[Cy.sub.3]]B[F.sub.4] a ete utilise comme composes de reference pour les determinations des p[K.sup.DM]. On a cree une echelle continue de valeurs de p[K.sup.DM] s'etalant de 9,7, a 5,7 en faisant appel aux composes acides [HP[R.sub.3]]B[Ph.sub.4]. Ces acides dont les valeurs de p[K.sup.DM] sont superieures a 6 sont stables alors que ceux des cations plus acides HP[R.sub.3.sup.+] se protonent au B[Ph.sub.4.sup.-] pour conduire a la formation de [R.sub.3]PB[Ph.sub.3] et de benzene. Les valeurs de p[K.sup.THF] rapportees dans la litterature pour les [HP[Bu.sub.2]Ph]B[Ph.sub.4], [HPMe[Ph.sub.2]]B[Ph.sub.4] et [HPEt[Ph.sub.2]]B[Ph.sub.4] ne sont pas fiables en raison de cette reaction de protonation. On a utilise les techniques d'effet Overhauser nucleaire et d'echo de spin a champ pulse PGSE en RMN du ¹H pour montrer que dans le DM, aux concentrations utilisees pour les Etudes acide-base, le [HP[Cy.sub.2]Ph]B[Ph.sub.4] existe sous la forme de paire d'ions et d'agregats plus importants allant jusqu'a des quadrupoles. La reaction du RuHCl[(P[Ph.sub.3]).sub.2](dach) et RuHCl{tme[P.sub.2][(NH).sub.2]} avec du HB[F.sub.4] a permid de preparer les deux nouveaux complexes de dihydrogene suivants [Ru([H.sub.2])Cl[(P[Ph.sub.3]).sub.2] (dach)]B[F.sub.4] (dach = (1R,2R)-(-)-diaminocyclohexane) et [Ru([H.sub.2])Cl{tme[P.sub.2][(NH).sub.2]}]B[F.sub.4] (tme[P.sub.2][(NH).sub.2] = P[Ph.sub.2][C.sub.6][H.sub.4] C[H.sub.2]NHC[Me.sub.2] C[Me.sub.2]NHC[H.sub.2][C.sub.6] [H.sub.4]P[Ph.sub.2]) dont on a determine les structures cristallines et les valeurs de p[K.sup.DM] de leurs sels B[Ph.sub.4.sup.-] qui s'etablissent respectivement a 8,6 et 6,9. Mots cles : acidite, complexe de dihydrogene, hydrure, phosphonium, dichloromethane. [Traduit par la Redaction], Introduction The quantitative study of the acidity of transition metal hydride and dihydrogen complexes serves to better the understanding of the reactions of these species in catalytic reactions, including those [...]

The synthesis and the qualitative interionic investigation in solution of trans-[Ru(COMe){(pz(sub 2))CH(sub 2)}(CO)(PMe(sub 3))(sub 2)]X (X(super _) = BPh(sub 4)(super -), BPh(sub 3)Me(super -), BPh(sub 3)(n-Bu)(super -), BPh(sub 3)(n-Hex)(super -), B(3,5-(CF(sub 3))(sub 2)(C6H3))(sub 4)(super -), PF(sub 6)(super -) and BF(sub 4)(super -), pz = pyrazol-1-yl-ring), complexes bearing both symmetric and unsymmetric counteranions are reported.

Research has been conducted on the ionic methylplatinum(II) complexes. The synthesis and characterization of these complexes have been carried out and the results indicate that all compounds feature static structure in solutions.