Four chiral square-planar (SP-4) alkynylplatinum (II) complexes Pt (L)(CC–Ph)(1), Pt (L)(CC– Ph–Br)(2), Pt (L)(CC–Ph–CH3)(3) and Pt (L)(CC–Ph–OCH3)(4)(L=(1S, 5S)-6, 6-dimethyl- 3′-(pyridin-2-yl)-4′ H-spiro [bicyclo [3.1. 1] heptane-2, 5′-isoxazole]) were prepared by the complexation of ligand L with K2PtCl4 and subsequent treatment with corresponding alkynes. Their structures were characterized by single crystal X-ray diffraction and ...