Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5221960 | Tetrahedron | 2011 | 8 Pages |
2-(ω-Chloroalkyl)tetramethoxycalix[4]arenes are converted to 2-(ω-azidoalkyl)tetramethoxy- and cone-2-(ω-azidoalkyl)tetrapropoxycalix[4]arenes, the former by substitution and the latter by demethylation to 2-(ω-chloroalkyl)tetrahydroxycalix[4]arenes, which are O-propylated before substitution of azide for chloride. The azide-terminated calixarenes undergo Cu(I)-catalyzed 1,3-cycloaddition to terminal alkynes to give 1,4-disubstituted 1,2,3-triazoles, demonstrating the potential to couple calixarenes from a tether at the 2-position (methylene bridge) to substrates that bear a terminal alkyne group. The cone conformation of cone-2-(4-chlorobutyl)tetrapropoxycalix[4]arene has been confirmed by X-ray diffraction.
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