Resorcinol-derived calixarenes

Figure 1.2 Phenol-derived and resorcinol-derived calixarenes...

Vocanson, F. Lamartine, R. Lanteri, P. Longeray, R. Gauvrit, J. Y. NewJ. Chem. 1995,19,825. The resorcinol-derived calixarenes, generally made via acid catalysis, have recently been found to be accessible by base-induced condensation as well Konishi, H. Iwasaki, Y. Morikawa, O. Okano, T. Kiji, J. Chem. Express 1990, 5, 869 Konishi, FI. Iwasaki, Y. Synlett 1995, 612. 

The calixarene family can be subdivided into two major branches, the phenol-derived cyclooligomers (2) and the resorcinol-derived cyclooligomers (3), as shown in Figure 1.2. Both are discussed in the previous volume. The present monograph, however, will deal almost exclusively with the phenol-derived compounds, the resorcinol-derived compounds having been the subject of a 1994 publication in Monographs in Supramolecular Chemistry and a long review article. ... 

Harrowfield, J.M. Richmond. W.R. Sobolev. A. Inclusion of quaternary ammonium compounds by calixarenes. J. Inch Phenoin. Mol. Recognit. Chem. 1994. 19. 257. Lippmann, T. Wilde. H. Pink. M. Schaefer. A. Hesse. M. Mann. G. Host-guest complexes between resorcinol-derived cal ix [4] arenas and alkyl ammonium ions. Angew. Chem. 1993, 105, 1258-1260. ... 

Calixarenes are macrocyclic molecules synthesized with high yield by condensation of appropriate arenes and aldehyde derivatives. Calix means bowF in Latin and Greek, and this phrase reflects the shape of the tetramer, which usually adopts a bowl or beaker-like conformation. Gutsche first introduced the name calixarene for this class of compounds [38]. Several authors have exhaustively reviewed the chemistry and synthetic procedures, which lead to different structural modifications of calixarenes [39-42]. In general, three types of calixarenes derivatives are known first, metacyclophanes (type 1) second, those obtained by condensation of formaldehyde with phenol (type 11), and third, those obtained by reaction with resorcinol (type III) (Scheme 6). The latter modifications are also called resorcarenes to distinguish calixarenes of type III from those of type II. 

Resorcinol and pyrogallol are benzene derivatives that have two and three hydroxyl groups, respectively. They react readily with aldehydes to form macrocycles that are similar in some aspects to the calixarenes [16]. The formation of calixarenes involves reaction of phenol at the 2,6-carbons, through which the methylene link forms. Resorcinol is 1,3-dihydroxybenzene, and as with pyrogallol, 1,2,3-trihydroxybenzene, the ring-forming links occur at the 4- and 6-positions. Exemplary structures are shown in Fig. 8.3. 

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