Synthesis and Conformational Studies on Hexa-<i>O</i>-alkyl p-Unsubstituted Calix[6]arenes
作者:José C. Iglesias-Sánchez、Beatriz Souto、César J. Pastor、Javier de Mendoza、Pilar Prados
DOI:10.1021/jo0516638
日期:2005.12.1
para-unsubstituted calix[6]arene 1 in rings 1 and 4 (2a−c) and the subsequent alkylation of phenol groups with α-haloesters (methyl esters 3a, 3c, and 3e; tert-butyl esters 3b, 3d, and 3f) to determine the effect of these groups on their conformational behavior. 2D NMR studies at 188 K reveal that compounds 2a−c, 3b, 3d, and 3f are less flexible, showing a 1,2,3-alternate conformation. The same conformation has been