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Assemblies between pseudo-enantiomers with different d8metal centers, Δ-[M(bpy){Co(aet)2(R-pn)}]3+(M = Pd or Pt, bpy = 2,2′-bipyridine, aet = 2-aminoethanethiolate, pn = 1,2-propanediamine), and Λ-[M′(bpy){Co(aet)2(S-pn)}]3+(M′ ≠ M, M′ = Pd or Pt), have been examined from stereo- and spectrochemical aspects. A mixture of equimolar amounts of the optically active sulfur-bridged dinuclear complex, Δ-[M(bpy){Co(aet)2(R-pn)}](NO3)3·7H2O, and its pseudo-enantiomer, Λ-[M′(bpy){Co(aet)2(S-pn)}](NO3)3·7H2O, in H2O crystallizes as [M(bpy){Co(aet)2(R-pn)}][M′(bpy){Co(aet)2(S-pn)}](NO3)6·4H2O, in which two complex cations with imperfect enantiomorphisms form a 1 : 1π–πstacked unit. [ABSTRACT FROM AUTHOR]

The reaction of N,N'-bis(2-hydroxybenzyl)-N,N'-bis(2-pyridylmethyl)-R-1,2-propanediamine (R-bbppnH2) with Ln(NO3)3 · nH2O (Ln = Tb, Dy, Ho, Er, Tm, Yb, or Lu) stereoselectively gave an optically active complex, [Ln(R-bbppn)(NO3)]. All the complexes crystallize in the same acentric orthorhombic space group of C2221. The central Ln(III) in the complex is coordinated by four oxygens from two phenolates of R-bbppn and one bidentate nitrate and by four nitrogens from two pyridines and one bidentate propanediamine of R-bbppn to form a distorted dodecahedral geometry. The combinations of four oxygens and four nitrogens afford two separate trapeziums, which are almost orthogonal to each other. Although two optical isomers, ΔΛΔ and ΛΔΛ, are possible for such a structure, the absolute configuration of the complex is stereoselectively unified to ΔΛΔ. Furthermore, two chiral nitrogens in the complex are fixed to R configurations, and the five-membered propanediamine and pyridylmethylamine chelate rings take λ and δ configurations, respectively. These stereoselectivities reflect an introduction of the optically active R-propanediamine moiety in the ligand. The electronic absorption, CD, and diffuse reflectance spectra, magnetic susceptibilities, and molar conductivities of the complexes are also discussed in conjunction with their structures. [ABSTRACT FROM AUTHOR]

Reaction of trans(N)-[Co(D-pen)2]- (pen = penicillaminate) or trans(N)-[Co(L-pen)2]- with [MCl2(L)] {M = Pd or Pt, L = 2,2'-bipyridine (bpy) or 1,10-phenanthroline (phen)} in the presence of tetrafluoroborate stereoselectively gave an optically active S-bridged dinuclear complex, [M(L){Co(D-pen)2}]BF4 · 2H2O or [M(L){Co(L-pen)2}]BF4 · 2H2O. The mixture of equimolar amounts of these enantiomers in H2O crystallizes as [M(L){Co(D-pen)2}]0.5[M(L){Co(L-pen)2}]0.5BF4 · 4H2O (DLbpyM · 4H2O, DLphenM-A · 4H2O), in which the enantiomeric complex cations are included by the ratio of 1 : 1. In crystals of DLbpyM · 4H2O and DLphenM-A · 4H2O, [M(L){Co(D-pen)2}]+ and [M(L){Co(L-pen)2}]+ interact stereospecifically with each other through π-conjugated systems to form dimeric structures. Other racemic crystals with the same chemical compositions as DLphenM-A · 4H2O, DLphenM-B · 4H2O, were obtained from equimolar amounts of [M(phen){Co(D-pen)2}]+ and [M(phen){Co(L-pen)2}]+ in aqueous acetonitrile solution. In the crystals of DLphenM-B · 4H2O, [M(phen){Co(D-pen)2}]+ and [M(phen){Co(L-pen)2}]+ are arranged alternately while overlapping phen planes, and the π electronic systems of phen interact with each other. Although stereospecific hydrogen bonds between the coordinated -NH2 and -COO- groups are formed in both DLphenM-A · 4H2O and DLphenM-B · 4H2O, their bonding modes differ noticeably from each other. As a result, DLphenM-A · 4H2O builds up 1-D ladder-like networks due to the stereospecific π-π stackings and hydrogen bondings between enantiomers, while 2-D sheet-like networks are established for DLphenM-B · 4H2O. [ABSTRACT FROM AUTHOR]

This study presents an empirical analysis of the reasons Japanese companies are pursuing subsidiary reacquisition, with a particular focus on listed subsidiaries. Based on previous research on listed subsidiaries, we identified and empirically analyzed five hypotheses regarding the motivation for pursuing reacquisition: the information asymmetry hypothesis, restructuring hypothesis, low growth hypothesis, conflict-of-interest hypothesis, and hostile merger and acquisition (M&A) hypothesis. The results did not offer support for the information asymmetry hypothesis, low growth hypothesis, or hostile M&A hypothesis, but did in part support the restructuring hypothesis and low growth hypothesis. They also showed that the restructuring hypothesis is the only one of these five that accounts for the possibility of an increase in the share value of the parent company. [ABSTRACT FROM AUTHOR]