Ligand Design for the Assembly of Polynuclear Complexes:  Syntheses and Structures of Trinuclear and Tetranuclear Aluminum Alkyl Complexes Bearing Tripodal Diamidoselenophosphinito Ligands and a Comparison to Related Tripodal Triamidophosphine Complexes

Abstract

Reactions of the triaminophosphines P(CH2NHArR)3 (1a−c, where ArR = 3,5-(CF3)2C6H3 for a; ArR = Ph for b, ArR = 3,5-Me2C6H3 for c) with selenium afford the triaminophosphine selenides SeP(CH2NHArR)3 (2a−c). The phosphine selenides 2a−c react with 4 equiv of AlMe3 at room temperature to generate the triangular trinuclear aluminum complexes [P(CH2NArR)2Se](AlMe2)3 (3a−c). The byproduct of the formation of 3a was hydrolyzed and provided CH3CH2N(H)-3,5-(CF3)2C6H3. When 2a−c are treated with excess AlMe3, the corresponding tetranuclear Lewis acid−base adducts Me3Al·[P(CH2NArR)2Se](AlMe2)3 (4b,c) are isolated. The reaction of P(CH2NHArR)3 (1a−c) with 2 equiv of AlMe3 produces the dinuclear aluminum complexes P(CH2NArR)3Al2Me3 (5a−c). When 1b,c are reacted with excess AlMe3, the Lewis acid−base adducts Me3Al·P(CH2NArR)3Al2Me3 (6b,c) are isolated. Solid-state molecular structures were determined for complexes 2a, 2b, 2c, 3a, 3c, 4b, 5a, and 6b by X-ray crystallography.

The coordination chemistry of selenophosphite ligands. Synthesis and characterization of heterometallic tetranuclear clusters [M{CpFe(CO)2P(Se)(OR)2}3](PF6) (M = Cu, Ag; R = nPr, iPr) and [Cu(μ-X) {CpFe(CO)2P(Se)(OiPr)2}]2 (X = Cl, Br)

“…The Cu-Se distance is 2.3505(7) A ˚slightly longer than 2.342(1)-2.343( 9 The P-Se bond distances in compound 6, 2.1707 (19) A ˚are slightly shorter than that of compound 5 [2.1781(16) A ˚] which is reflected from their P-Se coupling constants in 31 P NMR: 598 Hz in 6 and 568 Hz in 5. The Se-P-Fe angles in the compound 6, 113.84 (8) • , are different to those of 121.71(7) • observed in 5.…”

“…In addition, the bridging selenophosphinito (R 2 PSe − ) unit was also revealed in a tetranuclear Al III complex synthesized by Johnson and Han. 8 Recently, Rothenberger et al reported the generation of P-Se anions by breakage of the neutral group 15/16 ligand (Woollins reagent), which ultimately bridged copper via selenium and phosphorus atoms of the [(-O)(R)PSe] 2 2− unit to form cluster compounds. 9 In a search for heterometallic complexes containing a P-Se fragment where both P and Se atoms bridged metal centers; surprisingly, no single molecule with organoselenophosphorus ligands has been structurally characterized.…”

Tricarbonylmanganese(I) and –rhenium(I) Complexes of Imidazol‐Based Phosphane Ligands: Influence of the Substitution Pattern on the CO Release Properties

“…The IR stretching frequencies and chemical shifts of the 31 P NMR resonances of all complexes are reported in 3 . [29][30][31][32] The shift of the 31 P{ 1 H} NMR signal of 6, which is a classical coordination shift, is 15 ppm to a lower field.…”

Bridged Dinuclear Tripodal Tris(amido)phosphane Complexes of Titanium and Zirconium as Diligating Building Blocks for Organometallic Polymers

“…Recently, we reported the synthesis and initial study of the tripodal amido phosphane ligands of the type P(CH 2 NHAr R ) 3 [11][12][13] where Ar R is an aryl substituent. With metals in oxidation states greater than +3, these ligands preferentially form complexes where all three amido donors chelate to the metal, similar to other tripodal amido ligands.…”