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Three polymorphs of a novel naphthylimido derivative of hexamolybdate with crystal structure such as pseudohigher symmetry, helical chains, and [pi]-[pi] stacking which demonstrates the effect of solvent polarity and crystallization speed on polymorphism in organic-inorganic hybrids is presented.

The first polyoxometalatocyclophases are prepared by the covalent linkages of a hexamolybdate cluster and bisarylimido ligands containing flexible chains. A new protocol is described for preparing chiral polyoxometalates (POMs) and chiral metallamacrocycles from achiral building blocks by fastening both ends of a flexible chain onto an achiral POM to remove the symmetric center and mirror.

Several X-ray diffraction studies are conducted to explain the properties of the various nanoscale chiral rod-like molecular traids that are assembled from achiral polyoxometalates. These chiral nanostructures are shown to be widely used in numerous ferroelectric and asymmetric catalysis applications.

The synthesis of a kinetically controlled trans bifunctionalized organoimido derivative of hexamolybdate, n-Bu4N)2{trans-[Mo6O17(NAr)2]} (Ar = 2,6-dimethylphenyl) in ca. 60 percent yield under mild reaction conditions is discussed. Semiconductivity with an optical energy gap of 2.55 eV is observed in the compound.

A novel protocol is developed to produce C=C double bonds through the dehydrogenative coupling of [sp.sup.3] C-H bonds from aliphatic primary amines. The findings reveal that C=C double bonds can be obtained directly from the functionalization of two saturated C-H bonds and polymolybdates are found to be promising reagents in the activation of C-H bonds.

Four novel fluoro-functionalized arylimido-substituted hexamolybadates, ( n-Bu 4N) 2[Mo 6O 18(NAr)] (Ar = 2-CH 3-4-FC 6H 3( 1), 3-CH 3-4-FC 6H 3( 2), 4-FC 6H 4( 3), or 2-FC 6H 4( 4)), in which fluorinated phenylimido group linked to an Mo of hexamolybdate by a Mo−N triple bond, have been prepared via the DCC ( N, N′-dicyclohexylcarbodiimide) dehydrating protocol of the reaction of α-octamolybdate ion with 2-methyl-4-fluoroaniline hydrochloride, 3-methyl-4-fluoroaniline hydrochloride, 4-fluoroaniline hydrochloride, or 2-fluoroaniline hydrochloride in anhydrous acetonitrile. All these compounds have been characterized by elemental analysis, UV−vis, IR, 1H NMR, and single-crystal X-ray diffraction analyses. The preliminary biological activity test indicated that these compounds display potent herbicidal activity, in particular against the roots of some tested plants (such as Brassica campestris L., Eclipta prostrata L., Echinochloa crusgallis L., and Cirsium japonicum DC.). [ABSTRACT FROM AUTHOR]

A kinetically controlled trans bifunctionalized organoimido derivative of hexamolybdate, (n-Bu4N)2{trans-[Mo6O17-(NAr)2]} (Ar = 2,6-dimethylphenyl) 1, in which the two 2,6-dimethylphenylimido groups are bonded to hexamolybdate at the trans positions, has been successfully synthesized in ca. 60% yield under mild reaction conditions. Its trans structure has been confirmed by a single-crystal X-ray diffraction study. In the crystals, cluster anions of 1 self-assemble into a 3D netlike structure via two different kinds of C-H…O hydrogen bondings, in which 1D supramolecular rectangular channels containing tetrabutylammonium cations form along the a axis. Compound 1 has also been characterized by ¹H NMR, IR, and UV-vis spectroscopic studies. UV-vis-near-IR reflectance spectroscopy measurements reveal the compound's nature of semiconductivity with an optical energy gap of 2.55 eV. [ABSTRACT FROM AUTHOR]

The article reports on the study, which determines that two α C—H bonds in aliphatic primary amines can be activated by a polymolybdate, and a carbon—carbon double bond forms unexpectedly via the doubly dehydrogenerative coupling (DDHC) reaction. Accordingly, the formation of carbon—carbon double bonds is one of the most useful and fundamental reactions in chemistry.

Examines the synthesis of the first arylimido derivatives of mixed-metal polyoxometalates. Evaluation of the photophysical properties of the generated hybrid materials; Preparation of hybrid materials; Reactions between hexamolybdate and isocyanate.