1,3,5-Trisubstitution at the phenolic hydroxyls of p-tert-butylcalix[6]arene (1), previously obtained in sizeable yield only with Mel (Casnati ct al. J. Chem. Sec., Chem. Commun. 1991, 1413), has been now achieved by direct O-alkylation with alkyl iodides (Et, n-Pr, n-Bu) and p-X-benzyl bromides, (X = tert-Bu, Me, Br, NO2) in the presence of a weak base (K2CO3 or CsF). These results suggest that 1,3,5-trisubstitution can also be extended to other alkylating agents provided that an appropriate weak base is used. The 1,3,5-tris(p-X-benzyl) ethers 6-9, whose structure have been established by H-1-NMR spectral analysis and chemical correlation, in CDCl3 solution adopt a conformation with only a 2-fold symmetry element bisecting two aromatic rings.
Neri Placido, Consoli Grazia M. L., Cunsolo Francesca, Piattelli Mario, Tetrahedron Lett, 35 (1994) N 17, S 2795-2798
作者:Neri Placido, Consoli Grazia M. L., Cunsolo Francesca, Piattelli Mario
DOI:——
日期:——
Biomimetic Copper(I)-CO Complexes: A Structural and Dynamic Study of a Calix[6]arene-Based Supramolecular System
作者:Yannick Rondelez、Olivier Sénèque、Marie-Noëlle Rager、Arthur F. Duprat、Olivia Reinaud
calix[6]arene-based cuprous complexes are described. They present a biomimetic tris(imidazole) coordination core associated with a hydrophobic cavity that wraps the apical binding site. Each differs from the other by the methyl or ethyl substituents present on the phenoxyl groups (OR1) and on the imidazole arms (NR2) of the calix[6]arene structure. In solution, stable CO complexes were obtained. We have