Compounds noncyclic polyether

We have studied the synthesis of noncyclic polyether compounds and their cation transport behaviors (5), Recently, we found that the noncyclic polyether compounds containing oxytrimethylene chain units, e.g., jL, could transport lithium ion selectively as is shown in Fig. 1 and against its concentration gradient (5b, 5e). 

Noncyclic polyether compounds, 1 were prepared as previously-... 

It is necessary that not only free noncyclic polyether compounds but also their alkali salts can be dissolved into hydrophobic... 

On the basis of the consideration mentioned-above, some noncyclic polyether compounds were newly prepared and their ability in cation transport was examined by using them as a carrier. It is expected that polyether i exhibits the most excellent ability of selective transport among them because polyether 1 has been designed to form a spherical conformation with a thick hydrophobic external wall and deep pseudocavity according to the hypothesis proposed. Polyether, were prepared by the procedure as depicted in Scheme 2. 

In conclusion, these noncyclic polyether compounds result in the drastic change of their conformation by the uptake of cation(Scheme 3), that is, the formation of the hydrophobic wall, pseudocavity, and the stacking between aromatic rings, then the salt of the polyether carriers can be solubilized in organic solvent and diffused easily across a chloroform liquid membrane. Then, at the other boundary the smooth release of cation which is driven by proton potential occurs. 

Weber, E., Polytropic cation receptors. 2. Synthesis and selective complex formation of spiro-linked multitrop crown compounds,/. Org. Chem., 47, 3478, 1982. Goldberg, 1., Geometry of the ether, sulphide and hydroxyl groups and structural chemistry of macrocyclic and noncyclic polyether compounds, in The Chemistry of the Ether Linkage, Patai, E., Ed., Suppl. E, Part 1, Wiley, London, 1981, 175. 

So far several polyether family compounds exhibiting lithium ion-selectivity have been reported, e.g., 12-crown-4, 14-crown-4, macro-cyclic compounds having tetrahydrofuran as a chain component, cryptand [211], spherand, noncyclic diamide, and so on (2). However these are not always suitable to transport lithium ion selectively through liquid membranes. That is, these are useful as extracting agents or chemical devices for ion selective electrode (3), but are not available and... 

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