| Abstract
| - The molecular structures of the rubidium and cesium derivatives of supermesitylphosphane [i.e., (2,4,6- tBu3C6H2)PH2] as well as several base adducts of these are reported, showing a manifold of geometric variations of polymeric ladder-type structures in the solid state with each alkali metal cation coordinating to the π cloud of a neighboring supermesityl ring. E.g., a twist is observed in the infinitely extended Cs−P ladder (shown) of the pyridine adduct [{CsP(H)tBu3Mes}2(μ-pyridine)]x. Four asymmetric units compose one full cycle of a complete structural motif that is a ribbon that twists approximately 130° in one direction and then reverses and twists equally in the opposite direction.
- The molecular structures of the rubidium and cesium derivatives of supermesitylphosphane [i.e., (2,4,6-tBu3C6H2)PH2 = tBu3MesPH2] as well as several base adducts of these are reported. Sodium hydride, potassiumhydride, rubidium metal, and cesium metal react with tBu3MesPH2 in tetrahydrofuran solution at room temperatureto produce MPRH salts 1−4 [M = Na (1), K (2), Rb (3), Cs (4); R = tBu3Mes] in good yields. X-ray-qualitycrystals of 2 and 3 were obtained by slow evaporation of solutions of the corresponding MP(H)tBu3Mes speciesdissolved in toluene/thf. Complex 4 was crystallized from hot toluene. On the other hand, slow evaporation ofa toluene/tetrahydrofuran solution of CsP(H)tBu3Mes (4) produces crystals of the composition {[CsP(H)tBu3Mes]2(μ-THF)0.9·toluene}x (5). Crystallization of 4 in the presence of pyridine yields crystals of {[CsP(H)tBu3Mes]2(μ-pyridine)}x (6). Also, crystallization of complexes 3 and 4 from toluene/N-methylimidazole (N-MeIm)gives the isomorphous complexes {[RbP(H)tBu3Mes]2(μ-N-MeIm)}x (7) and {[CsP(H)tBu3Mes]2(μ-N-MeIm)}x(8), respectively. However, crystallization of 4 from toluene in the presence of bidentate or polydentate basessuch as dimethoxyethane or pentamethyldiethylenetriamine does not result in incorporation of these bases intothe lattice. Instead, the toluene solvate {[CsP(H)tBu3Mes]2(η3-toluene)0.5}x (9) is obtained. On the other hand,crystallization of 4 from toluene/ethylenediamine gives the base adduct {[CsP(H)tBu3Mes]2(μ-ethylenediamine)}x(10). Complex 3 crystallizes in the triclinic space group P1̄. Crystal data for 3 at 218 K: a = 6.71320(10) Å,b = 10.5022(2) Å, c = 14.9733(3) Å, α = 91.3524(13)°, β = 102.5584(13)°, γ = 107.7966(14)°; Z = 1; R1 =6.55%. Complex 4 crystallizes in the triclinic space group P1̄. Crystal data for 4 at 223 K: a = 7.0730(14) Å;b = 10.395(2) Å; c = 14.933(2) Å; α = 81.97(1)°; β = 76.35(2)°; γ = 71.824(14)°; Z = 1; R1 = 4.56%.Complex 5 crystallizes in the monoclinic space group P21/c. Crystal data for 5 at 243 K: a = 15.039(2) Å; b= 16.152(3) Å; c = 20.967(5) Å; β = 91.53(2)°; Z = 4; R1 = 4.83%. Complex 6 crystallizes in the orthorhombicspace group Pbcn. Crystal data for 6 at 298 K: a = 14.686(2) Å; b = 21.295(5) Å; c = 28.767(5) Å; Z = 8;R1 = 5.61%. Complex 7 crystallizes in the orthorhombic space group Pbcn. Crystal data for 7 at 218 K: a =14.5533(2) Å; b = 21.4258(5) Å; c = 28.5990(5) Å; Z = 8; R1 = 4.61%. Complex 8 crystallizes in theorthorhombic space group Pbcn. Crystal data for 8 at 219 K: a = 14.6162(2) Å; b = 21.3992(3) Å; c = 28.7037(2) Å; Z = 8; R1 = 3.57%. Complex 9 crystallizes in the triclinic space group P1̄. Crystal data for 9 at 293 K: a = 11.147(4) Å; b = 14.615(4) Å; c = 14.806(5) Å; α = 70.57(3)°; β = 71.85(3)°; γ = 72.93(2)°; Z = 2; R1= 5.13%. Complex 10 crystallizes in the triclinic space group P1̄. Crystal data for 10 at 173 K: a = 10.5690(4)Å; b = 15.0376(5) Å; c = 15.3643(5) Å; α = 111.8630(10)°; β = 100.4120(10)°; γ = 97.4820(2)°; Z = 2; R1= 4.87%. A common feature of the molecular structures of complexes 2−10 is an infinitely extended polymericladder framework in the solid state. Both solution and solid-state NMR data are presented.
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