Azocalix[4]pyrroles: one-pot microwave and one drop water assisted synthesis, spectroscopic characterization and preliminary investigation of its complexation with copper (II)

Heterocalixarenes and Calixnaphthalenes

“…This has allowed the syntheses of a variety of tetrasubstituted calix [4]pyrroles with a variety of groups. 84 These could then be further reacted with diazonium salts to make a series of azobenzene-derived calix [4]pyrroles; examples of two of these are shown in Figure 5.34f,g. One of these ( Figure 5.34c) was found to be capable of forming a complex with two VO 2 + ions where the hydroxamic acid units are thought to complex the vanadium atoms and the pyrroles hydrogen-bond to one of the oxygens.…”

Calix[n]pyrroles as Anion and Ion-Pair Complexants

“…Recent advances in the synthesis of this macrocycle include microwave-assisted synthesis of calix [4]pyrroles containing hydroxamic acids [26] and azo-functionalized derivatives [27]. Amberlyst TM -15 has been employed by Chauhan and co-workers as a solid acid catalyst, which can be removed from the reaction conveniently by filtration [28] whilst Kulkarni and co-workers have used molecular sieve MCM-41 as a heterogeneous catalyst for calixpyrrole synthesis [29].…”

Tetra-azobenzene extended calix[4]pyrroles: influence of photo-isomerization on chloride binding and its transport through liposomal membranes

“…Other tetra-azobenzene extended C [4]P have been previously reported, but their photoisomerization behaviors and binding properties were not described. 17,18 Very recently, Wezenberg and co-workers reported the synthesis of a strapped calix [4]pyrrole receptor with a stiff-stilbene unit incorporated in the strap. 19 The switching of the stilbene unit between its Z and E forms significantly reduced the size of the macrocyclic anion binding pocket delimited by the strap.…”