Calix resorcinarene

Rose, K. N., Barbour, L. J., Orr, G. W., Atwood, J. L., Self-assembly of carcerand-like dimers of calix[4]resorcinarene facilitated by hydrogen bonded solvent bridges. Chem. Commun. 1998, 407-408. 

Figure S. Structure of hydrophobically substituted calix[4]resorcinarene adsorbed onto silica-based resin for HPLC separations (see ref 21).

Among more complex macrocycles, Li et al. [47-52] reported the preparation and characterization of stationary phases incorporating calixarenes or calix-crowns bonded to silica. With individual columns, high selectivity was observed in the separation of alkylated aromatics, aromatic carboxylic acids, sulfonamides, nucleosides, and water-soluble vitamins. In other work, Sokoliess et al. [53] have characterized calixarene- and resorcinarene-bonded stationary phases similar to those described in the previous section of this chapter. And Huai et al. [54] used an end-capped p-tert-butyl-calix[4]arene-bonded silica phase for HPLC separation of a number of organic compounds. Resorcinarenes have also found application in GC. [55-57] Recently, exotic macrocycles have been used in capillary electrochromatography, as reported by Gong et al. [58]... 

Pietraszkiewicz, O. and Pietraszkiewicz, M. (1999) Separation of Pyrimidine Bases on a HPLC Stationary RP-18 Phase Coated with Calix[4]resorcinarene, J. Incl. Phen. 35, 261-270. 

Fig. 37. (Top) Formulae of calix[4]resorcinarenes (middle) formulae of calix[n]arenes (bottom) X-ray structures of (left) calix[4]resorcinarene (MacGillivray et al., 2001) and (right) p-tert-butylcalix[4]arene (Ungaro et al., 1985).

Shevchuk and coworkers have performed systematic investigations of Ndm and Ybm 1 1 complexes with a series of calix[4]resorcinarenes and calix[4]arenes. A first study aimed at establishing an analytical procedure for the determination of these two ions in organic solvents. The intrinsic luminescence of the ligand is quenched when Ybm chloride is added to the so-... 

Figure 11.1. Calix[4]resorcinarene, which forms a snub cube with 60 hydrogen bonds.

Calix[4]resorcinarenes, which can be used as supramolecular building blocks, have been prepared in high yields and purity using a solvent free approach. Equimolar quantities of the benzaldehyde and resorcinol, in the presence of /7-toluenesulfonic acid, were ground together using a mortar and pestle... 

Figure 2.2 Solvent free synthesis of calix[4]resorcinarene.

PPG 425 has been used in the preparation of a range of benzaldehydes that were subsequently used in the solvent free synthesis of calix[4]resorcinarenes. The aldehydes are isolated in near quantitative yields by distillation from the PPG, which can be recycled. PPG has also been used in the indium metal mediated allylation of imines and sulfonylimines. Ultrasound was used for two reasons to clean the metal surface and to increase the solubility of the imine in PPG. The solvent was recycled three times, but a desire to develop an easier drying and recycling method was indicated. 

In addition to crown-ethers, calix[4]resorcinarenes 19 have also been used as head groups to obtain azobenzene amphipbiles with sufficient photo-isomerization in LBK films. For this purpose, azobenzene moieties have been tethered to the lower rim of the crown conformer of the calixarene. O-octacarboxymethoxylated calix[4]resorcinarenes 19 (X = CH2-COOH) display efficient trans to cis photoisomerizability in densely packed mono-layers on a water surface, in LBK films, and in surface-adsorbed monolayers, whereas the noncarboxymetylated 19 (X = H) derivative gives films that are too densely packed. However, the aggregation is already suppressed efficiently compared to the azobenzene derivative without calixaren. ... 

Kurita, E., Fukushima, N., Fujimaki, M., Matsuzawa, Y., Kudo, K., and Ichunura. K. Macrocyclic amphiphiles. Part 2. Multi-point adsorptivitiy of the crown con former of calix[4]resorcinarenes and their derivatives on surfaces of amorphous polar substrates. /. Mater. Chem., 8, 397 (1998). 

Oh, S.-K, Nakagawa, M., and Ichimura, K. Self-assembled monolayers derived from calix[4]resorcinarenes exhibiting excellent desorption-resistance and their applicability to surface energy photocontrol. Chem. Lett., 349 (1999). 

Pietraszkiewicz M, Kozbial M, and Pietraszkiewicz O. Transport studies of inorganic and organic cations across liquid membranes containing Mannich-base calix[4]resorcinarenes. Pol J Chem, 1998 72(5) 886-892. 

Resorcinarenes, macromolecules of type III, are an interesting class of compounds through their prospective applications as molecular devices for molecular recognition, HPLC experiments, ion transport across membranes, etc. Much attention has recently been paid to solid state NMR studies of the tetra(C-undecyl)calix[4]resorcinarene host obtained from resorcinol and lau-ryl aldehyde (Scheme 8) [55,56]. 

Analysis of CP kinetics and the parameters obtained are a source of important information about host-guest interactions. From the classic I-S model of cross polarization, it was found that the values of T pH relaxation times for guest and host molecules are considerably different. This suggests that DMF carbons cross-polarize from the DMF protons, not from the remote protons, of calixarene. Moreover, such a result proves that the DMF is located outside the calices and between the calixarene molecules. The simple I-S model is not sufficient to describe the cross-polarization of the complex of tetra (C-undecyl)calix[4]resorcinarene with DMA. The best fit of experimental data was seen when the more advanced I-F-S model of cross polarization was adopted [57]. Analysis of CP kinetic parameters provides important information on molecular mobility (Fig. 19, Table 5). 

Another example of bidentate diphenoxide binding was demonstrated by the metallation of calix-4-resorcinarenes with zirconocene fragments. The resulting organometallic product contained four Zr atoms, each bound to the phenolate groups in a bidentate fashion.504... 

Early reports on AFM studies on calix[4]resorcinarene and calix[4]arene sulfide molecules [150, 151], suggested, that the calixarenes self-organize in monolayers on Au(lll) surfaces, however, they did not identify a molecular ordering. 

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