Improved syntheses of a series of [(L) 2 Pt(η 2 -nb)] (4)–(8) (L=PPh 3 , 1/2 dpp(o-xyl), 1/2 dppb, 1/2 dppbe, 1/2 dppn) complexes are described. Complexes 4–8 have been characterized by 1 H, 31 P NMR, IR spectroscopy as well as mass spectrometry and elemental analysis. The reaction of [(dppbe)Pt(Cl 2 )] with sodium borohydride and tolan was investigated by 31 P NMR spectroscopy. The complex [(dppbe)Pt(η 2 -tolan)] (11) has been isolated and characterized. The reactivity of [(dppn)Pt(η 2 -nb)] with the spirocyclohexyl-1,2,4-trithiolane 12 and the sterically hindered 2,2,4,4-tetramethyl-3-thioxocyclobutanone 13 was tested. The complex [(dppn)Pt(η 2 –13)] (14) has been isolated and characterized by 1 H, 31 P NMR, IR spectroscopy as well as mass spectrometry and elemental analysis. X-ray crystal analyses have been performed on complex 8, 11 and 14.