Calix arene acetylation

K. Krenek, M. Kuldova, K. Hulfkova, I. Stibor, P. Lhotak, M. Dudic, J. Budka, H. Pelantova, K. Bezouska, A. Fiserova, and V. Kren, /V-Acetyl-D-glucosamine substituted calix[4]arenes as stimulators of NK cell-mediated antitumor immune response, Carbohydr. Res., 342 (2007) 1781-1792. 

The bromination and acetylation reactions show that the calixarenes are capable of undergoing conventional electrophilic substitution reactions without rupture of the macrocyclic ring. Zinke et al.18) reported the nitration of p-tert-butylcalixarene (ring size uncertain) and obtained a material that failed to melt up to 400 °C, exploded when heated more strongly, and had a nitrogen analysis in agreement with a tetranitro-calixarene. Attempts to obtain a nitration product from calix[4]arene 59,... 

Scheme 56. Preparation of calixarene-core multifunctional initiators and the structure of calix [4] arene modified with acetyl chloride groups [346]...

Calixarenes a group of compounds first observed many years ago (ref. 90) have been studied intensively only in the last few years. Their chemistry has been reviewed (ref.91,92). Calix[4]arene in dichloromethane was acetylated with acetyl chloride in the presence of aluminium chloride to give a 4,4 -diacetyl derivative in 63% yield without the formation of any 0-acetyl isomers (ref.93). 

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