ZINC DIMERIZATION OF P-TERT-BUTYLCALIX[4]ARENE

Reaction of p-tert-butylcalix[4]arene, 1, with excess ZnEt(2) results in complete metallation of the calixarene, or with two equivalents of ZnEt, selective dimetallation occurs yielding the his(calix[4]arene) s pecies [{1-H-2)Zn}(2)], 2; distorted four coordinate O-bound zinc cent ers (Zn-O = 1.895(7) - 1.978(8) Angstrom) fuse the slightly flattened cone conformation calixarene units with methylene chloride included in the divergent cavities.