Synthesis and Characterization of Platinum Ethylene Complex

n-Octyl iodide (0.5 mL, 2.7 mmol) was added to a suspension of [Pt(dmphen)(ethene)] (0.43 g, 1.0 mmol) in 5 mL of dry toluene and the mixture was stirred at room temperature. After 1 h, n-hexane was added to complete the precipitation of a yellow solid, which was recovered and washed with n-hexane. The solid was dissolved in dichloromethane, and the solution was filtered on a thin pad of FLORISIL^® (100–200 mesh) and crystallized with n-hexane (light brown solid—yield: 65%). ¹H NMR (500 MHz, 298 K, CDCl₃): δ 8.31 (d, 2H, J = 8.2 Hz, H4 and H7 dmphen), 7.85 (s, 2H, H5 and H6 dmphen), 7.77 (d, 2H, J = 8.2 Hz, H3 and H8 dmphen), 3.33 (s, 6H, Me dmphen), 3.31 (dd, 2H, J_Pt = 85.2 Hz, H ethene—partially overlapped), 2.22 (dd, 2H, J_Pt = 62.0 Hz, ethene), 1.14–0.7 (m, 12H, H_aliphatic), 0.75 (t, 3H, J = 7.3 Hz, Me aliphatic), and 0.36–0.23 (m, 2H). ¹³C NMR (125.7 MHz, 298 K, CDCl₃): δ 161.2 (x2, C2 and C9 dmphen), 145.2 (x2, C10a and C10b dmphen), 137.3 (x2, C4 and C7 dmphen), 128.5 (x2, C4a and C6a dmphen), 126.1 (x2, C5 and C6 dmphen), 125.8 (x2, C3 and C8 dmphen), 31.7, 31.0 (x2), 30.7 and 30.3 (5 CH₂), 29.2 (x2, Me dmphen), 28.9 (x2) (ethene, J_Pt = 382 Hz), 22.6 (CH₂), 19.6 (PtCH₂, J_Pt = 638 Hz), and 14.1 (Me).