Mark F. Self

On the organoaluminum chemistry of multidentate phosphine ligands. Reaction of trimethylaluminum with bis(diphenylphosphino)methane: Synthesis and molecular structure of [Al(CH3)3]2[(C6H5)2PCH2P(C6H5)2]

Reaction of an excess of trimethylaluminum with bis(diphenylphosphino)-methane in heptane affords the crystalline complex [A1(CH3)3]2[(C6H5)2PCH2P(C6H5)2]. The title compound crystallizes in the triclinic space group P¯1 with unit cell parametersa=10.053(6),b=11.017(6),c=15.908(8) Å,α=85.58(4),β=71.80(4), γ=77.49(4)°,V=1634(1) Å3, andDc=1.07 g cm−3 forZ=2. Least-squares refinement based on 2924 observed reflection with intensitiesI≥3σI) in the range 2.00≤2θ≤45.0° converged atR=0.050 (Rw=0.067). The Al-P distances are 2.585(2) and 2.521(2) Å, and the P-C-P angle is 121.4(2)°.

Reaction of organoaluminium species with bidentate phosphine ligands. Synthesis and molecular structure of [AlCl3][(Ph2P)2CH2][AlCl2(CH3)] and [AlCl3]2[(Ph2P(O))2CH2]

Reaction of methylaluminium sesquichloride with bis(diphenylphosphino) methane and bis(diphenylphosphinoyl)methane affords [AlCl3][(Ph2P)2CH2][AlCl2(CH3)] (I) and [AlCl3]2[(Ph2P(O))2CH2] (II), respectively. Compound I crystallizes in the triclinic space group P−1 with unit cell parameters a = 10.009(3), b = 10.748(4), c = 14.806(5) A, α = 90.38(3), β = 103.36(2), γ = 96.89(3)°, V = 1537.5 A3 and ϱ = 1.36 for Z = 2. Compound II crystallizes in the monoclinic space group C2 with unit cell parameters a = 12.773(2), b = 13.028(3), c = 9.461(2) A, β = 104.43(2)°, V = 1524.60 A3 and ϱ = 1.49 for Z = 2. Full-matrix least-squares refinement based on 3034 observed reflections for I converged at R = 0.047 (Rw = 0.066); full-matrix least-squares refinement based on 1565 observed reflections for II converged at R = 0.043 (Rw = 0.050). Both products result from reaction of the disproportionation products of methylaluminium sesquichloride, AlCl3 and AlCl2(CH3).

Unexpected Conformation of the Hydrogen Chloride Salt of [14]aneN4: An X-ray Structural Examination of [H2[14]aneN4H2]C14 and its Role in Organoaluminum Host-Guest Chemistry

Abstract The macrocyclic salt [H2[14]aneN4H2]Cl4 was prepared and its X-ray crystal structure was determined. The salt crystallizes in the orthorhombic space group Pnna with unit cell parameters a α 14.257(11), b α 7.796(5), c α 17.785(9) A3, V = 1976.8(2) A3, and D c α 1.28gcm-3 for Z α 4. Least-squares refinement based on 1086 observed reflections (I > 3[sgrave](I)) converged at R α 0.055 (R w α 0.075). The macrocyclic cation is in an unusual exodentate conformation. Additionally, the X-ray crystal structure of the uncomplexed macrocyclic tetradentate secondary amine [14]aneN4 was determined. The neutral macro-cycle crystallizes in the triclinic space group P1 with unit cell parameters a α 4.698(3), b α 8.683(5), c α 15.388(12) A, α α 90.63(6), β α 97.38(6), γ α 98.99(5)[ddot], V α 614.6(8) A3, and D c α 1.08 gem-3 for Z α 2. Least-squares refinement based on 1458 observed reflections (I >3[sgrave](I)) converged at R α 0.086 (R w α 0.116). The endodentate conformation of the neutral macrocycle is stabil...

Reaction of trimethylaluminium with sulphur derivatives of bis(diphenylphospino)methane and bis(diphenylphosphino)ethane. Synthesis and molecular structure of [Al(CH3)2][(C6H5)2P(S)CHP(S)(C6H5)2][Al(CH3)3] and [Al(CH3)3]2[(C6H5)2P(S)CH2CH2P(S)(C6H5)2]

Abstract Reaction of trimethylaluminium with bis(diphenylthiophosphinoyl)methane and bis(diphenylthiophosphinoyl)ethane affords the crystalline compounds [Al(CH 3 ) 2 ][(C 6 H 5 ) 2 P(S)CHP(S)(C 6 H 5 ) 2 ][Al(CH 3 ) 3 ] ( I ) and [Al(CH 3 ) 3 ] 2 [(C 6 H 5 ) 2 P(S)CH 2 CH 2 P(S)(C 6 H 5 ) 2 ] ( II ), respectively. Compound I crystallizes in the monoclinic space group P 2 1 / n (No. 14) with unit cell parameters a = 18.126(2), b = 9.569(2), c = 19.394(3) A, β = 110.20(1)°, V = 3156.7(7) A 3 , and ϱ = 1.21 g cm −3 for Z = 4. Least-squares refinement based on 2891 observed reflections [ I > 3σ( I )] converged at R = 0.040, R w = 0.051. Compound II crystallizes in the triclinic space group P 1 (No. 2) with unit cell parameters a = 12.076(3), b = 13.148(3), c = 13.114(3) A, α = 98.32(2), β = 100.55(2), γ = 116.41(2)°, V = 1772.1(7) A 3 , and ϱ = 1.14 g cm −3 for Z = 2. Least-squares refinement based on 3012 observed reflections [ I > 3σ( I )] converged at R = 0.049, R w = 0.056. Compound I results from a unique condensation reaction in which one of the central methylene CH bonds was cleaved in addition to one AlCH 3 bond, resulting in an unusual AlPSC four-membered ring. The length of the hydrocarbon chain in bidentate phosphine ligands appears to play an important role in their reactivity with organo-aluminium species, as reaction of bis(diphenylthiophosphinoyl)ethane with trimethylaluminium did not facilitate condensation, but resulted in an addition compound, II . These results demonstrate a comparatively greater acidity of the hydrocarbon chain hydrogen atoms of bis(diphenylthiophosphinoyl)methane relative to bis(diphenylthiophosphinoyl)ethane.

Reaction of Trimethylaluminum with 3-Amino-5,6-Dimethyl-l,2,4-Triazine. Synthesis and Molecular Structure of [(Al(CH3)2)]5[C11H15N8][AI(CH3)31; a Highly Aggregated Al-N System

Abstract Reaction of trimethylaluminum with 3-amino-5,6-dimethyl-l,2,4-triazine in toluene affords the crystalline product [(Al(CH3)2)]5[C11H15N8][Al(CH3)3] (I). (I) crystallizes in the triclinic space group PI (No. 2) with unit cell parameters a = 11.081(4), b = 12.807(4), c = 16.519(5) A, a = 91.95(3), β = 104.86(3),γ = 101.89(3)[ddot], V = 2208(1) A3, and ρ = 1.07 g cm−3 for Z = 2. Full-matrix least-squares refinement based on 3217 observed reflections with intensities I > 3σ(I) in the range 3.50 ≤ 20 ≤ 45.0[ddot] converged at R = 0.066, R w = 0.085. The mean Al-N bond length is 1.957(6) A. The core of the molecule contains an eight-membered A12N4C2 ring bisected by a bridging dimethylaluminum unit.

Reaction of Diisobutylaluminum Hydride with Bis(Diphenylphosphinoyl)Ethane. Synthesis and Structure of [AI(C4H9)3]2[dppe]

Abstract Reaction of an excess of diisobutylaluminum hydride with bis(diphenylphosphinoyl)ethane (dppe-O2), the di-oxygen derivative of bis(diphenylphosphino)ethane (dppe), in heptane affords the crystalline product [AI(C4H9)3]2[dppe]. The title compound crystallizes in the triclinic space group PI with unit cell parameters a = 9.514(3), b = 10.417(4), c = 13.364(4) A, α = 97.67(3), β = 102.09(2), Δ = 95.49(3)°, V= 1273.1(7)A3, and D c = 1.04g cm−3 for Z= 1. Least-squares refinement based on 2455 observed reflections (I > 3σ (I)) converged at R = 0.059, R w = 0.070. The title compound results from a unique reaction wherein dppe and triisobutylaluminum were generated in situ from dppe-O2 and diisobutylaluminum hydride, respectively.