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A new series of cationic heterodinuclear complexes, [M1M2Cl2(meso‐dpmppp)(RNC)2]PF6 (M1=Ni, M2=Rh, R=tBu (1 a); M1=Pd, M2=Rh, R=tBu (2 a), Xyl (2 b); M1=Pt, M2=Rh, R=tBu (3 a), Xyl (3 b); M1=Pd, M2=Ir, R=tBu (4 a)), supported by a tetradentate phosphine ligand, meso‐Ph2PCH2P(Ph)(CH2)3P(Ph)CH2PPh2 (meso‐dpmppp), were synthesized by stepwise reactions of meso‐dpmppp with NiCl2 ⋅ 6H2O or MCl2(cod) (M=Pd, Pt), forming mononuclear metalloligands of [M1Cl2(meso‐dpmppp)], and with [M2Cl(cod)]2 (M2=Rh, Ir) and RNC (R=tBu, Xyl) in the presence of [NH4][PF6]. The related neutral PdRh complex, [PdRhCl3(meso‐dpmppp)(XylNC)] (5), was also prepared. The structures of 1–5 were determined by X‐ray analyses to contain two square planar d8 metal centers with face‐to‐face arrangement, where meso‐dpmppp supports M1 and M2 metal ions in cis/trans‐P,P coordination mode, combining cis‐{M1P2Cl2} and trans‐{M2P2(CNR)2} units. Complexes 1–4 showed an intence characteristic absorption around 422–464 nm derived from RhI→RNC MLCT transition (HOMO→LUMO+1), which are influenced by changing M1 (NiII, PdII, PtII) metal ions since HOMO composed of dσ* orbitals appreciably destabilized by changing M1 from Ni to Pd, and Pt. The electronic structures of 1 a–4 a were investigated on the basis of DFT calculations and NBO analyses to show weak but noticeable d8–d8 metallophilic interaction as empirical dispersion energy of 0.9–1.5 kcal/mol without M1–M2 covalent bonding interaction. In addition, 1–5 were utilized as catalysts for hydrosilylation of styrene, and the NiRh complex 1 a was found to show higher activity and chemo‐ and regioselectivity compared with 2–5. [ABSTRACT FROM AUTHOR]

With the hope of tuning structural and electronic properties of the metal chains by changing the N‐substituent group and P‐chiral configurations, a series of PNP bridged tetraphosphines, rac‐ and meso‐Ph2PCH2P(Ph)N(Ar)P(Ph)CH2PPh2 (Ar=4‐RC6H4, R=F (rac‐dpmppanF), CH3 (rac‐dpmppanMe), H (meso‐dpmppan), OMe (meso‐dpmppanOMe); Ar=2,4‐xylyl (rac‐dpmppanMe2)), were synthesized, and utilized to prepare the Pd4 and Pt2Pd2 chains with XylNC terminal ligands, [M4(rac‐dpmppanR)2(XylNC)2](PF6)2 (M4=Pd4, R=F (1F), Me (1Me); M4=Pt2Pd2, R=F (4F), Me (4Me)) and [M4(meso‐dpmppanR)2(XylNC)2](PF6)2 (M4=Pd4, R=H (6), OMe (6OMe); M4=PdPt2Pd, R=OMe (9OMe)). While the M4 metal chains with rac‐dpmppanR (R=H, F, Me) ligands showed only marginal effects on the tetranuclear metal chains, the meso stereoisomer of meso‐dpmppanOMe afforded a new series of Pd4 (6OMe), PtPd3 (7OMe), PtPd2Pt (8OMe), PdPt2Pd (9OMe), Pt3Pd (10OMe), and Pt4 (11OMe) chains that exhibited a characteristic electronic absorption band tunable by the number and positions of incorporated Pt atoms from 628 nm to 473 nm. Especially, 11OMe is the first example of Pt4 chains supported by tetraphosphines. The coordinatively unsaturated Pd4 strings, [Pd4(rac‐dpmppan)2(CH3CN)](BF4)2 (12) and [Pd4(meso‐dpmppanOMe)2](BF4)2 (13), were also synthesized and 12 was utilized in axial ligand exchange reactions with PPh2Me, and PPh3 to disclose their successive incorporation into [Pd4(rac‐dpmppan)2(L)2](BF4)2 (L=PPh2Me (14 a), PPh3 (14 b)) and remarkable red‐shift (713–718 nm) of the HOMO‐LUMO transition of the Pd4 chains. The linear Pd4, PtnPd4‐n (n=1–3), and Pt4 complexes obtained in the present study could be useful 1D building blocks for assembling through metal−metal interaction. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of tri- and tetranuclear Cu(II) complexes utilizing mononuclear Cu(II) chiral building block with the sugar-derived Schiff's base ligand H3L(super 1) are reported. The results help in creating an efficient method for constructing chiral multinuclear complexes by utilizing the mononuclear {Cu(HL(super 1))} chiral building blocks.

A P‐stereogenic linear tetraphosphine tetraoxide, (R,R)‐ or (S,S)‐dpmppm(=O)4, was synthesized to prepare C2 dinuclear M(hfa)3 complexes (M=Eu, Tb, Y) as the first example of lanthanide(III) complexes with P‐chiral multidentate phosphine oxides. The mononuclear M(hfa)3 complexes (M=Eu, Y) with a P‐chiral diphosphine dioxide, tpdpb(=O)2, were also prepared, and comparison of their photophysical properties for the EuIII complexes revealed that significant chiral induction from the P‐chiral centers arises on the achiral M(hfa)3 units through intramolecular π‐π stacking constraint in the dinuclear system. [ABSTRACT FROM AUTHOR]

Research has been conducted on the 1,3-propanadiamine derivatives connected to carbohydrates and prepared from peracetylated sugar and 1,3-dibromo-2-propanol. Anomeric configurations and sugar puckering conformations have been investigated via X-ray crystallography of diazido precursors.

Research has been conducted on the heptadentate N-glycoside ligand mononuclear manganese(II) complexes. The use of X-ray crystallography has been described.

The linear Pd8 complex supported by tetraphosphines reacted with HBF4 to give an unprecedented linear tetrapalladium complex with a terminal hydride, which promoted electrocatalytic hydrogen formation from HBF4 in acetonitrile. The 1D coordination polymer of Pd8 chain confined within Nafion film was applied to the electrocatalytic H2 formation. [ABSTRACT FROM AUTHOR]

Carbohydrates are widely occurring and are needed by living organisms. Naturally rare carbohydrates are involved in glycoproteins, glycolipids and antibiotics. The syntheses and structural determinations of novel seven-coordinated cage-type cobalt(II) compounds, containing N-glycosides from mannose-type aldoses is reported.

Incorporation of a monovalent group 11 metal ion (Au(I), Ag(I) or CU(I)) with d10 configuration into the Pt2 core has led to the formation of heterotrimetallic Pt2M complexes. The PtCuX assembly forms a rhombic structure when CuX fragment was introduced. The reactions could help in the synthesis of other heterotrinuclear complexes. The angle of Pt...Cu-X is less than 90 degrees resulting in a short interatomic distance between the terminal Pt and X atoms.

The synthesis and characterization of carboxylate-bridged dimagnesium(II) complexes containing the dinucleating XDK ligand where H2XDK = m-xylylenediamine bis(Kemp's triacid imide) were carried out. Consequently,, carboxylate- and phosphodiester-bridged dimagnesium(II)-XDK, dicalcium(II)-XDK and dizinc(II)-XDK complexes were prepared and found to be catalysts in the cleavage of phosphate ester bonds.

The reaction of (RuCl2(dmso)4) with dhptaH5 (1,3-diamino-2-hydroxypropane tetraacetic acid) and carboxylate ligands afforded diruthenium(III) complexes, M(Ru(dhpta)(mu-O2Cr)2). The complexes arer soluble and retain the dinuclear structure in water. They thus offer a good basis for clarifying redox properties of the diruthenium center. X-ray crystallography and EXAFS analysis were used to characterize the complexes.

Aldoses are coordinated on nickel(II) ion using the N-glycosidic bond formation with tris(2-aminoethyl)amine (tren). Specifically, mono-, bis- and tris-(sugar)complexes are synthesized and characterized. For example, (Ni tren H2O2)X2, where X = Cl, Br and X2 = SO4, reacts with mannose-type aldoses of 2,3-cis configuration (D-mannose and L-rhamnose) to yield bis(N-aldosyl-2-aminoethyl)(2-aminoethyl)amine nickel(II) complexes (Ni N,N'-aldosyl sub 2-tren)X2. The resulting complexes are characterized by X-ray analyses.

The reactions of linear trinuclear platinum complexes with small organic molecules yields asymmetrical A-frame triplatinum complexes. The complexes possess an extra bridge across one of the metal-metal bonds. The trinuclear complexes serve as models for the study of the interactions between small molecules and the surfaces of heterogeneous catalysts. The reactions of a linear triplatinum complex with electron deficient HBF4.Et2O and p-NO2C6H4NC are discussed.

The addition of Zn(acac)2.2H2O to [Zn(XDK)(H2O)] XDK mononuclear zinc complex will produce the dizinc compound [Zn2(XDK)(acac)2(CH3OH)2]. [Zn2(XDK)(acac)2(CH3OH)2] has four discrete molecules in its unit cells intermolecular contacts. [Zn(XDK)(H2O)] acts as a precursor to zinc-containing carboxylate-bridged heterodimetallic complexes. The Zn to M distance is linearly coordinated with the ionic radius of high-spin octahedral M ions. Carboxylate-bridged divalent heterodinuclear compounds acts models for heterodimetallic centers in nonredox metalloenzymes.