Two chiral mononuclear and one-dimensional cadmium(II) complexes constructed by (1R,2R)-N1,N2-bis(pyridinylmethyl)cyclohexane-1,2-diamine derivatives: Effect of positional isomerism

Reactions of (1R,2R)-N1,N2-bis(pyridinylmethyl)cyclohexane-1,2-diamine derivatives, (1R,2R)-2-bpcd and (1R,2R)-3-bpcd [(1R,2R)-2-bpcd = (1R,2R)-N1,N2-bis(pyridin-2-ylmethyl)cyclohexane-1,2-diamine, (1R,2R)-3-bpcd = (1R,2R)-N1,N2-bis(pyridin-3-ylmethyl)cyclohexane-1,2-diamine], with CdI2 in an analogous way led to the formation of a chiral discrete mononuclear complex and a chiral one-dimensional polymeric chain, respectively, which may be attributed to the positional isomerism of the ligands. The chiral organic ligands and complexes display luminescent properties indicating that they may have a potential application as optical materials. Powder second-harmonic generation (SHG) efficiency measurement shows that the SHG efficiency of the complexes is approximately 0.3 and 0.45 times that of KDP, respectively.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Two chiral complexes have been synthesized via (1R,2R)-1,2-diaminocyclohexane derivatives and CdI2 in an analogous way. ► The difference of their structures can be attributed to the positional isomerism of the ligands. ► The chiral organic ligands and complexes have potential applications as optical materials.