Two one-dimensional intercalating molybdenum oxide polymers have been synthesized using different structure-directing units under specific hydrothermal conditions. MoO-0 (NaNH4Mo3O10) was synthesized using tetramethylammonium hydroxide, and MoO-1(C6H18N2Mo4O13) was synthesized using 1,6-hexanediamine. The two crystal structures have been determined by the single-crystal X-ray diffraction method. Both consist of bundles of parallel molybdenum oxide chains interspersed with metals or organic cations which play the role of intercalating agent in the host structure. The Mo has a 6+ valence state and distorted octahedral coordination. Mo-0 has orthorhombic symmetry (Pnma, No. 62) with a = 8.407(2) Å, b = 7.603(2) Å, and c = 14.350(3) Å. MoO-1 has triclinic symmetry (P1̄, No. 2) with a = 8.267(2) Å, b = 8.986(2) Å, c = 12.714(3) Å, α = 87.58(3)°, β = 76.48(3)°, γ = 67.97(3)°. The study suggests that the structures and properties of intercalation-type molybdenum oxide polymers can be engineered by incorporating the structure-directing units, acidity, and the hydrothermal conditions.

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The ortho palladation of prochiral (di-tert-butyl)(diphenylmethyl)phosphine proceeded readily to give rise to the dimeric complex, di-mu-chlorobis{[(phenyl)(di-tert-butylphosphino)methyl]phenyl-C2, P}dipalladium(II). The (S,S)-(+)-dimer was subsequently obtained by optical resolution with sodium (S)-prolinate. The absolute configuration of the optically resolved (+)-dimer was concluded from the X-ray diffraction studies of the derivatized O,O-acetylacetonate complex. The availability of the (+)-dimer is crucial to the study of the properties of the Pd-C bond. The phosphapalladacycle Pd-C bond exhibited a remarkable thermodynamic stability. It could not be permanently ruptured to give rise to the eta1-P monodentate even in a refluxing acetone solution containing concentrated hydrochloric acid. Instead, the phosphine was noted to fluctuate between the ring closed and opened states via the reversible Pd-C bond cleavage/formation under this condition. Inevitably, this resulted in the racemization of the five-membered organopalladium ring structure. In contrast, such bond cleavage was not observed at room temperature in the absence of HCl. In fact, the phosphine was observed to readily ortho palladate even under conditions not favorable to cyclopalladation. Indeed, the difficulty of isolating the phosphine as a simple eta1-P monodentate coordination complex was further noted by its lack of reactivity toward the N,N-dimethyl-1-(1'naphthyl)ethylaminate palladacycle mu-chloro dimer. Only by enhancing the Lewis acidity of the palladacycle in the form of the positively charged bis(acetonitrile) complex could the phosphine be encouraged to participate in monodentate eta1-P bonding. Even then, this form of coordination was weak and was only observed by NMR spectroscopy.

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