In situ single‐crystal to single‐crystal (SCSC) transformation of the one‐dimensional polymer catena ‐poly[[diaqua(sulfato)copper(II)]‐μ 2 ‐glycine] into the two‐dimensional polymer poly[μ 2 ‐glycine‐μ 4 ‐sulfato‐copper(II)]

The one‐dimensional coordination polymer catena ‐poly[diaqua(sulfato‐κ O )copper(II)]‐μ 2 ‐glycine‐κ 2 O : O ′], [Cu(SO 4 )(C 2 H 5 NO 2 )(H 2 O) 2 ] n , (I), was synthesized by slow evaporation under vacuum of a saturated aqueous equimolar mixture of copper(II) sulfate and glycine. On heating the same blue crystal of this complex to 435 K in an oven, its aspect changed to a very pale blue and crystal structure analysis indicated that it had transformed into the two‐dimensional coordination polymer poly[(μ 2 ‐glycine‐κ 2 O : O ′)(μ 4 ‐sulfato‐κ 4 O : O ′: O ′′: O ′′)copper(II)], [Cu(SO 4 )(C 2 H 5 NO 2 )] n , (II). In (I), the Cu II cation has a pentacoordinate square‐pyramidal coordination environment. It is coordinated by two water molecules and two O atoms of bridging glycine carboxylate groups in the basal plane, and by a sulfate O atom in the apical position. In complex (II), the Cu II cation has an octahedral coordination environment. It is coordinated by four sulfate O atoms, one of which bridges two Cu II cations, and two O atoms of bridging glycine carboxylate groups. In the crystal structure of (I), the one‐dimensional polymers, extending along [001], are linked via N—H...O, O—H...O and bifurcated N—H...O,O hydrogen bonds, forming a three‐dimensional framework. In the crystal structure of (II), the two‐dimensional networks are linked via bifurcated N—H...O,O hydrogen bonds involving the sulfate O atoms, forming a three‐dimensional framework. In the crystal structures of both compounds, there are C—H...O hydrogen bonds present, which reinforce the three‐dimensional frameworks.