•N-Arylation of sulfonamides with arylboronic acids using PS-tet-Cu(II) in water.•The catalyst was characterized using the powder XRD, SEM, EDS and FT-IR spectroscopy.•The catalyst can be recovered and reused several times without significant loss of its catalytic activity.•Operational simplicity, green reaction conditions, short reaction times and high yields. This paper reports on the synthesis and use of nanopolymer supported copper (II) complex, as separable catalysts for N-arylation of sulfonamides with arylboronic acids in water. This method has the advantages of high yields, elimination of homogeneous catalysts, green reaction conditions, simple methodology and easy work up. The catalyst can be recovered and reused several times without significant loss of its catalytic activity. The catalyst was characterized using the powder XRD, SEM, EDS and FT-IR spectroscopy.