Calix arenes reaction with 2 pyridine

For achieving deep cavities in higher level supramolecular structures, lower rim conjugates 51-53 of calix[6]arene and pyridine having larger sized linkers have been obtained by 3-fold reactions of 2-[4-(bromomethyl)phenyl]pyridine, 5-(bromomethyl)-2-phenylpyridine and 5-(bromomethyl)-2-[9,9-di-M-hexylfluorenyl]pyridine with 1,3,5-trimethyl ether of the p-bu -calix[6]arene in the presence of NaH. These conjugates elaborated mainly cone conformations (2006JCXH9589). 

But in most macrocyclizations, thermodynamic control is not yet possible. These macrocyclizations have therefore been carried out under kinetic control, often using high dilution conditions. Typical reactions are the formation of lactams, for instance, in the second macro-cyclization during the synthesis of concave pyridines 1 by reaction of the macrocyclic diamines 8 with diacid dichIorides. or the reaction of calix[6]arene with... 

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