Abstract:The 1 H-NMR shifts of the imidazolium protons of some novel dimeric ionic liquids were examined in various deuterated solvents. Interactions between the solvent and the imidazolium salt of butyl substituted ionic liquids were observed to give higher chemical shifts than methyl substitution.

The synthesis of substituted imidazolium type ionic liquids via a simple method is described. Our synthesized ionic liquids are more useful in the catalytic behavior of Mannich reaction.

Annularly functionalized dicationic benzimidazolophanes (1, 2, and 3) and benzotriazolophanes (1a, 2a, and 3a) were synthesized by alkylation followed by double quaternization.Cationic heterophanes [1] are rapidly developing classes of cyclophanes, which mimic molecular recognition events in biological systems by apolar complexation of guest molecules in aqueous solution. Some of the important application aspects of cationic heterophanes are their ability to show increased chelating effects, solubilizing power,

P e r m a n e n t F l u o r e s c e n c e S e n s i n g H y p e r b r a n c h e d D e n d r i t i c A r c h i t e c t u r e s Abstract: A hyperbranched dendrimer with m-terphenyl as surface group and an anthraquinone core unit was synthesized and was found to display permanent fluorescence sensing even under highly acidic condition. Supramolecular systems with fluorescence tags play an important role in biology. 1 Photocurable, 2 photochromic 3 and water-soluble dendrimers 4 have been reported previously. Though anthracene-based dendrimers have been reported recently. 5 anthraquinone systems are fascinating chromophores due to their high fluorescence activity. The advantage of having an anthraquinone core is that, due to their fluorescence activity, the mobility of the supramolecular dendritic arms in biological systems can be easily monitored. Though some fluorescence sensing dendrimers have been reported, 6 the dendritic core loses fluorescence activity under acidic conditions and hence cannot function as a permanent fluorescence sensing material.We report herein the synthesis of anthraquinone based dendrimers 1a, 1b and 1c with m-terphenyl as the surface end group. The advantage of having the m-terphenyl surface group 7 is that the dendritic arm can be hyperbranched. Further more dendrimers 1a, 1b and 1c (Figure 1) show fluorescence activity even under highly acidic conditions and hence could be potential permanent fluorescence sensing tags.Synthesis of dendrimer 1a was achieved by alkylation of 1,5-dihydroxyanthraquinone (4) with m-terphenyl bromide 3. Methyl m-terphenyl (2) was obtained by the application of the Hart reaction. 8 Reaction of 3.1 equivalents of phenyl magnesium bromide with 2,6-dibromo 4-iodotoluene gave methyl m-terphenyl 2 in 78% yield, which on further reaction with NBS, 9 gave the bromomethyl m-terphenyl (3) in 82% yield. Reaction of 2.1 equivalents of the m-terphenyl bromide 3 with 1.0 equivalent of 4 afforded the dendrimer 1a 10 in 33% yield (Scheme 1)In the 1 H NMR spectrum, 1a displayed a singlet for the methylene protons at d = 5.30 ppm in addition to the aroFigure

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