Syntheses and Molecular Structures of Novel Alkali Metal Tetraorganylcyclopentaphosphanides and Tetraorganyltetraphosphane‐1,4‐diides

Abstract

The reaction of sodium with RPCl2 and PCl3 (12:4:1) in THF gives Na[cyclo‐(P5R4)] [R = iPr (1), Ph (2)], while four equivalents of RPCl2 [R = Ph, 2,4,6‐Me3C6H2 (Mes), tBu] react with ten equivalents of sodium sand or elemental potassium in refluxing THF to yield the compounds [Na2(THF)5(P4Ph4)] (3), [Na2(THF)4(P4Mes4)] (4), and [Na2(THF)4(P4tBu4)] (5), or the potassium salt [K2(THF)6(P4Mes4)] (6). Recrystallizing 6 from 1,4‐dioxane/pentane (1:3) also led to [{K(L)2}2{K(L)}6(P4Mes4)4·0.5THF]∞ (L = 1,4‐dioxane) (7). In the solid state, compounds 3−6 exist as isolated ion‐contact complexes, in which the P4 chain of the (P4R4)2− ligand has a syn arrangement, while a polymeric helical arrangement was observed for 7. A minor product, [{K(pmdeta)(HP3Mes3)}2{K2(P4Mes4)}]·0.25hexane (8), was isolated from the reaction of MesPCl2 and K (1:2.5). Compound 8 contains the first structurally characterized example of a triphosphanide anion, (HP3Mes3)−, besides K2(P4Mes4). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

Understanding the Conformational Dependence of Spin–Spin Coupling Constants: Through‐Bond and Through‐Space J(31P,31P) Coupling in Tetraphosphane‐1,4‐diides [M(L)x]2[P4R4]

“…Most notably, however, delocalization of the negative charge from the terminal P A atoms (the formal bearers of the negative charge) towards the cen-tral P B atoms (and to the associated hydrogen atoms) is much more pronounced in the type I than in the type II systems. This confirms roughly the structure-based "bond topology" indicated in Figure 1, [12] even though the distinction in the drawing may be exaggerated. In any case, interactions between metal cations and P A atoms are more pronounced for the type II structures, in keeping with the larger influence of the cations on the spin-spin couplings.…”

“…[12] In contrast, [Na(thf) 2,5 Figure 1), with coordination only to the terminal phosphorus atoms of the tetraphosphane-1,4-diide anion. The most characteristic structural feature of this arrangement, which was already proposed by Baudler and co-workers for these species in solution, [13] is the formation of fivemembered chelate rings between the tetraphosphanediide ligand and the alkali metal cations.…”

“…[12] prior to publication. We are also grateful to M. Westerhausen (Jena) and to V. G. Malkin (Bratislava) for helpful discussions.…”

Synthese und Molekülstruktur der Cu4P8‐Käfigverbindung [Cu4(P4Ph4)2(PCyp3)3]

“…[9,10] Eine Renaissance der Oligophosphanidchemie hat unter anderem zur gezielten Synthese von Na[cyclo-(P 5 tBu 4 )] geführt, das eine äußerst vielseitige Koordinationschemie aufweist, [14,15] sowie zur vereinfachten Synthese der Alkalimetalloligophosphandiide M 2 (P n R n ) (n = 2-4), [16][17][18] die detaillierte Untersuchungen zu Strukturprinzipien dieser Verbindungsklasse ermög-lichte. [16][17][18][19][20] Im Rahmen unserer Studien zu Metallkomplexen mit Oligophosphanidliganden [14][15][16][17][18][19][20][21] Im Unterschied dazu enthalten andere Kupfer(i)-Phosphanidokomplexe in der Regel vier-bis achtgliedrige Cu n P nRinge. [23,24] In Verbindung 1 wird das Kupferion Cu2 zusätz-lich durch ein Tricyclopentylphosphanmolekül koordiniert und weist daher eine verzerrt-tetraedrische Koordination auf.…”

“…Alle Lösungsmittel wurden durch Destillation gereinigt, getrocknet, mit Argon gesättigt und über Kaliumspiegel aufbewahrt. [Na 2 (thf) 4 (P 4 Ph 4 )] (2) wurde nach einer Literaturvorschrift synthetisiert; [16] alle anderen Reagentien wurden von Abbildung 2. Die Käfigstruktur von 1 (nur die Cu-und P-Atome sind gezeigt).…”