Synthesis, structure and inclusion properties of cone-tris{[(5′-methyl-2,2′-bipyridyl)-5-yl]oxycarbonylmethoxy}hexahomotrioxacalix[3]arene

A Hexahomotrioxacalix[3]arene-Based Ditopic Receptor for Alkylammonium Ions Controlled by Ag+ Ions

“…In agreement with its C 3 -symmetric cone -in conformation, receptor cone - 1 displays the following characteristic 1 H and 13 C-NMR spectroscopic features: (1) the cone - 1 conformation is firmly established by the presence of the bridging methylene protons that have a Δδ separation between H ax and H eq of Δδ 0.41 ppm in the 1 H-NMR spectrum (CDCl 3 ). In the calix[4]arenes, the Δδ values of the ArCH 2 Ar methylene protons have been correlated with the orientation of the adjacent aromatic rings [ 33 , 34 ] and similar findings were previously observed with hexahomotrioxacalix[3]arenes [ 12 , 13 ]. (2) The 13 C-NMR spectrum of receptor cone - 1 in CDCl 3 exhibited two peaks at δ 31 and 34 ppm for the tert -butyl carbons and a single peak at δ 69 ppm for the -O C H 2 - bridge linker carbons [ 35 ].…”

“…For example, calix[4]arene derivatives incorporating crown ethers, amides, esters, and carboxylic acid groups have been shown to selectively extract metal ions [ 10 ]. Hexahomotrioxacalix[3]arenes, which are structurally related to both calixarenes and to crown ethers, have a three dimensional cavity with a potentially C 3 -symmetric structure, and have been shown to be useful ligands for metal cations [ 11 , 12 , 13 , 14 ], ammonium cations [ 15 , 16 ], and fullerene derivatives [ 17 , 18 ].…”

Synthesis and structures of O-anthrylmethyl-substituted hexahomotrioxacalix[3]arenes

“…Hexahomotrioxacalixarenes are a class of synthetic macrocycles having phenolic units linked by CH 2 OCH 2 bridges, and their trimer has been widely used as a platform to generate versatile hosts for metal cations [12][13][14][15][16][17][18][19], ammonium cations [20][21][22], and fullerene derivatives [23][24][25]. In most cases, the functionalization of hexahomotrioxacalix [3]arene has been achieved by O-alkylation of the OH groups at the lower rim.…”