tetrahedro‐Tetraphosphorus as Monodentate Ligand in a Nickel(0) Complex

Early-Transition-Metal-Mediated Activation and Transformation of White Phosphorus

“…His research group found that treatment of a nickel (0) complex, Ni(np 3 ) (np 3 = N(C 2 H 4 PPh 2 ) 3 ), with P 4 in THF gave rise to the complex (P 4 )Ni(np 3 ) with the P 4 unit bonded to the metal atom by an apical P atom in an η 1 fashion. 46 Two years later Sacconi's group provided the second well-characterized example of a tetrahedro tetraphosphorus ligand, this time on Pd and supported by the related triphos ligand (triphos = MeC(CH 2 PPh 2 ) 3 ). 47 The chemical literature possessed these two as its only examples of an intact P 4 tetrahedron serving as a 2e ligand atop a transition metal complex for over twenty years despite a surge in the study of P 4 activation chemistry.…”

Synthesis, Characterization and Hydrolysis of Osmium Tetraphosphorus Complexes

“…[6,7] Indeed, while the range of P x topologies which may be generated from P 4 is enormous, the number of coordination complexes featuring the intact cage molecule as a ligand was, until a few years ago, limited to very few examples of species thermally unstable and/or difficult to handle. [8][9][10][11] Accordingly, the reactivity of the coordinated molecule has been scarcely investigated. In contrast to this general belief, we have found recently that 16-electron d 7 -metal complexes of rhenium, [12] iron [13] and ruthenium [13][14][15] may coordinate the intact P 4 molecule to readily form mono-and bimetallic compounds in good yield.…”

Metal-Mediated Degradation and Reaggregation of White Phosphorus

“…Indeed, with the Only the P-bonded carbon atoms of the cyclohexyl substituents are shown for the sake of clarity. Adapted from [16] single exception of 1, which was completely insoluble in common solvents [13], all the known tetrahedro-P 4 complexes, in the absence of additional coupling to NMR active nuclei (usually P-atoms of ancillary phosphanes or the metal itself), feature a well resolved AB 3 splitting pattern in the very high field region of the spectrum. The three uncoordinated phosphorus atoms (P B ) have exohedral sp 3 hybridized lone pairs and therefore may still act as a donor towards further transition-metal moieties.…”

“…Transition metal complexes featuring an intact, tetrahedro-tetraphosphorus ligand, i.e., h 1 -P 4 metal complexes, are quite scarce despite the increasing interest in this chemistry and the growth of the general knowledge concerning the reactivity of white phosphorus with transition metal species [3][4][5][6][7][8][9][10][11][12].Until a few years ago,the seminal complexes [(NP 3 )M(h 1 -P 4 )] (M=Ni, 1; Pd, 2), prepared in the late 1970s by Sacconi and coworkers by treating the strong Lewis acid complexes [(NP 3 )M] (M=Ni, 3 [13]; Pd, 4 [14]) with white phosphorus in THF/benzene solution (Eq. 1), remained the only well documented members of this class of compounds:…”