Supplementary information files for Dinuclear Palladium(II) and Platinum(II) Complexes of a Readily Accessible Bicyclic Diphosphane

<strong>Supplementary information files for article Dinuclear Palladium(II) and Platinum(II) Complexes of a Readily Accessible Bicyclic Diphosphane</strong> <br> The one-step synthesis (33 % isolated yield) of a novel bicyclic diphosphane, [P(CH₂)₂NC₆H₄(₄-NMe₂)]₂, P−P(NMe₂), from the reaction of [P(CH2OH)4]Cl and H₂NC₆H₄(₄-NMe₂) in methanol is described. Surprisingly, P−P(NMe₂) displays excellent air/solution stability (towards H₂O, CH₃OH) and can also function efficiently as a bridging ligand. Hence reaction of P−P(NMe₂) with [Pd(μ−Cl)(η³-allyl)]₂ (η³-allyl=C₃H₅, C₄H₇) or [Pd(μ−Cl)(κ²−C9H12N)]₂ affords the singly-bridged complexes {Pd(Cl)(η3-allyl)}2 {μ-P−P(NMe2)} 1 a/1 b and {Pd(Cl)(κ²−C9H12N)}₂{μ-P−P(NMe2)} 1 c whereas treatment with [MX2(η⁴-cod)] (M=Pd, Pt; X=Cl, Br, I, Me; η gave the corresponding dimethylammonium salts 3 a–d. Single crystal X-ray studies have been undertaken on P−P(N⁴-cod=cycloocta-1,5-diene) gave (MX2)2{μ-P−P(NMe2)}₂ 2a–e in high yields. Protonation of 2 a–d with HBF4 ⋅ OEt2Me2), 1 b, 2 a, 2 b ⋅ 2CDCl₃₂, 2 d, 2 e, 3 a ⋅ 12CD₃CN and 3 b ⋅ 12CD₃CN. The P−P bond lengths in free/coordinated P−P(NMe²) remain similar across all compounds studied here and no M ⋅⋅⋅ M contacts were observed within the planar M2P4 ring. In 3 a/3 b the BF4− anion displays a unique secondary interaction with the inorganic six-membered M2P4 core.