A novel heterogeneous copper nano catalyst supported on modified silica mesopore KIT-5 was successfully prepared. The 3-aminopropyltriethoxysilane (APTES) on KIT-5 was coordinated with copper(I) and accurately characterized. In addition a comparative survey on the metal-ligand interactions in the syntheses of catalyst in two different solvents via density functional theory calculations was performed. A one-pot procedure for syntheses of 1,4-disubstituted 1,2,3-triazole derivatives via a three-component reaction between terminal alkynes, alkyl halides, and sodium azide, namely click reaction in the presences of 3 mol% nanoparticles copper/APTES-KIT-5 (Cu/AK) as a catalyst was developed to give the products in good to excellent yields. This catalyst showed high catalytic activity in water as a "green" solvent. This reaction was performed under open air conditions and required no special reaction conditions and chromatographic separation for purification. (C) 2015 Elsevier B.V. All rights reserved.