Lower Rim Esters

Much more effective than the simple ethers in most cases are members of a family of compounds with the general structure 128 (see ref. 1, pp. 162-164 ref. 11, pp. 127-172), which have been studied with great zeal by a number of groups in recent years, particularly by McKervey and coworkers, as discussed in the next several subsections. 

However, an X-ray structure of the Ag complex of the tetramethyl ether of calix[4]arene shows it to be in the partial cone conformation Xu, W. Puddephatt, R. J. Muir, K. W. Torabi, A. A. Organometallics 1994, 13, 3054. 

Earliest to be studied among this family of compounds were esters 

Arnaud-Neu, F. Fanni, S. Guerra, L. McGregor, W. Ziat, K. Schwing-Weill, M.-J. Barrett, G.  

Stability constants for esters determined in MeOH or MeCN generally mimic the results obtained from extraction experiments the values for which 

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