First use of p-tert-butylcalix[4]arene-tetra-O-acetate as a nanoreactor having tunable selectivity towards cross azo-compounds by trapping silver ions

p-tert-Butylcalix[4]arene-tetra-O-acetate was established for the first time as a member of the nanoreactor series, even without having any OH group. The nano range distribution of this nanoreactor was ascertained by DLS, SEM and TEM studies. The capability of this cavitand towards hosting amines in a competitive manner generates a new green pathway for cross coupling of aromatic amines to give the corresponding azo-compounds. In this context, using p-tert-butylcalix[4]arene-tetra-O-acetate as a nanoreactor and silver nitrate as a catalyst, we got the cross azo-compound in good to excellent yields in the eco-friendly solvent water. This green methodology is also applicable for the synthesis of respective homo-compounds.