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Molecular‐level understanding of metal‐mediated white phosphorus (P4) activation is meaningful but challenging because of its direct relevance to the conversion of P4 into useful organophosphorus compounds as well as the complicated and unforeseeable cleavage process of P−P bonds. The related study, however, has still rarely been achieved to date. Here, a theoretical insight into the step‐by‐step process of three P−P bond cleavage/four P−C bond formation for [P3+P1]‐fragmentation of P4 mediated by lutetacyclopentadienes is reported. The unique charge‐separated intermediate and the intermolecular cooperation between two lutetacyclopentadienes play a vital role in the subsequent P−P/P−C bond breaking/forming. It is found that, although the first P−C formation is involved in the assembly of the cyclo‐P3 [R4C4P3]− unit, the construction of the aromatic five‐membered P1 heterocycle [R4C4P]− is completed prior to the cyclo‐P3 formation. The reaction mechanism has been carefully elucidated by analyses of the geometric structure, frontier molecular orbitals, bond index, and natural charge, which greatly broaden and enrich the general knowledge of the direct functionalization of P4. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: Studies on the aggregation degrees of negatively charged phosphides derived from the nucleophilic P4 functionalization could help understand the pathway of phosphorus atoms degradation or aggregation. In this report, we have isolated and characterized four phosphorus cluster anions (P73–, P144–, P162–, and P264–) from the nucleophilic functionalization of P4 with 1,4‐dilithio‐1,3‐butadienes. These phosphorus clusters could be rationalized as the P‐atom‐containing products besides the main phospholyl lithium. Their structural features and 31P NMR behaviors are discussed based on single crystal X‐ray diffraction analysis and 31P{1H} COSY NMR analysis. We have isolated and characterized four phosphorus cluster anions including Li3(THF)6P7, Li4(THF)10P14, Li2(THF)6P16 and Li4(THF)13P26 from the nucleophilic functionalization of white phosphorus with 1,4‐dilithio‐1,3‐butadienes. Their structural features and NMR behaviors are discussed based on X‐ray diffraction analysis and low‐temperature 31P{1H} COSY NMR analysis. [ABSTRACT FROM AUTHOR]

The [3+1] fragmentation reaction of rare-earth metallacyclopentadienes 1 a- c with 0.5 equivalents of P4 affords a series of rare-earth metal cyclo-P3 complexes 2 a- c and a phospholyl anion 3. 2 a- c demonstrate an unusual η3 coordination mode with one P−P bond featuring partial π-bonding character. 2 a- c are the first cyclo-P3 complexes of rare-earth metals, and also the first organo-substituted polyphosphides in the category of Group 3 and f-block elements. Rare-earth metallacyclopentadienes play a dual role in the combination of aromatization and Diels-Alder reaction. Compounds 2 a- c can coordinate to one or two [W(CO)5] units, yielding 4 a- c or 5 c, respectively. Furthermore, oxidation of 2 a with p-benzoquinone produces its corresponding phospholyllithium and regenerated P4. [ABSTRACT FROM AUTHOR]

The selective construction of P−C bonds directly from P4 and nucleophiles is an ideal and step-economical approach to utilizing elemental P4 for the straightforward synthesis of organophosphorus compounds. In this work, a highly efficient one-pot reaction between P4 and 1,4-dilithio-1,3-butadienes was realized, which quantitatively affords phospholyl lithium derivatives. DFT calculations indicate that the mechanism is significantly different from that of the well-known stepwise cleavage of P−P bond in P4 activation. Instead, a cooperative nucleophilic attack of two C [ABSTRACT FROM AUTHOR]

Yb3+/Er3+, Yb3+/Tm3+, or Yb3+/Er3+/Tm3+ (25, 1, and 0.5 mol%, resp.) co-doped Ca9Y(PO4)7 are prepared by hydrothermal reaction of a stoichiometric solution of CaCO3, Y2O3, and lanthanide oxides in HNO3 to which (NH4)2HPO4 is added at a controlled pH of 8 (autoclave, 200 °C, 10 h) followed by annealing in air (850 °C, 2 h). [ABSTRACT FROM AUTHOR]