Mesomorphic dimeric compounds consisting of rigid mesogenic cores and flexible oxyethylene chains have been prepared as liquid-crystalline materials capable of complexing with
ionic species. The incorporation of LiCF3SO3 into these materials results in the induction of
smectic A phases and significant mesophase stabilization. The ion−dipole interactions
between lithium ions and oxyethylene moieties have stabilized the mesomorphic layer
structures. Ionic conductivities have been measured for the complexes forming homeotropically aligned molecular orientation of smectic phases. The highest value of conduction,
which is observed for the direction parallel to the layer in the smectic A phase, is 5.5 × 10-4
S cm-1. These results suggest that the complexes of LiCF3SO3 with mesogenic rod−coil−rod molecules containing oxyethylene chains can function as self-organized ion conductive
materials.
Hydroamination, the formal addition of an N À H bond across a CÀC unsaturated bond, is a highly desirable and atomeconomical process for the preparation of amine derivatives.[1] It is known that hydroamination of alkenes and alkynes can be catalyzed by 1) organolanthanides, [2] 2) alkali metals, [3] 3) early (Ti, Zr) [4] and 4) late (Pd, Rh, Ru, Ir, Ni, Au) [5] transition metals, and 5) heterogeneous systems.[6]Depending on the catalytic system, an activation of either the CÀC multiple bond or the NÀH bond takes place; the former activation occurs in the case of (4), and the latter type takes place in the cases of (1)-(3). Concerning the latter type, the NÀH bond is converted into either metal-imide intermediates (for example, RN = Ti) or metal-amide intermediates (for example, R 2 N À Ln). Two other important aspects of hydroamination are a) the relative difficulty in achieving intermolecular hydroamination as compared to the intramolecular version and b) the relative ease in achieving the hydroamination of alkynes compared to that of alkenes. Concerning the hydroamination of allenes, [7] the intramolecular reaction is well-studied in comparison with the
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