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Dipnictenes of the type RPn=PnR (Pn=P, As, Sb, Bi) can be viewed as dimers of the corresponding pnictinidenes R−Pn. Phosphanylidene‐ and arsanylidenephosphoranes (R−Pn(PMe3); Pn=P, As) have been shown to be versatile synthetic surrogates for the delivery of pnictinidene fragments. We now report that thermal treatment of 1 : 1 mixtures of R−P(PMe3) and R'−As(PMe3) gives access to arsaphosphenes of the type RP=AsR'. Three examples are presented and the properties and reactivity of Mes*P=AsDipTer (1) (Mes*=2,4,6‐tBu3‐C6H2; DipTer=2,6‐(2,6‐iPr2C6H3)2‐C6H3) were studied in detail. Solid state 31P NMR spectroscopy revealed a large 31P NMR chemical shift anisotropy with a span of ca. 920 ppm for 1 while computational methods were employed to investigate this pronounced magnetic deshielding of the P atom in 1. In the presence of the carbene IMe4 (IMe4=:C(MeNCMe)2) 1 is shown to be split into the corresponding NHC adducts Mes*P(IMe4) and DipTerAs(IMe4), which is additionally shown for diarsenes. [ABSTRACT FROM AUTHOR]

Phosphaalumenes are the heavier isoelectronic analogs of alkynes and have eluded facile synthesis until recently. We have reported that the combination of a phosphinidene transfer agent, ArTerP(PMe3) (ArTer=2,6‐Ar2‐C6H3), with (Cp*Al)4 (Cp*=C5(CH3)5) afforded the phosphaalumenes ArTerPAlCp* as isolable, violet, thermally stable compounds. In here we describe attempts to utilize Mes*P(PMe3) (Mes*=2,4,6‐tBu3‐C6H2) as a phosphinidene source in combination with different Al(I) precursors, namely DipNacnacAl (DipNacnac=HC[C(Me)NDip]2, Dip=2,6‐iPr2‐C6H3), (Cp*Al)4 and Cp3tAl (Cp3t=1,2,4‐tBu3‐C5H2). In all cases the formation of phosphaalumenes was not observed, however, their intermediate formation is indicated by formation of the dimer [Cp*Al(μ‐PMes*)]2 (2) and C−H‐bond activation products along the putative P=Al bond, giving unusual 1,2‐P,Al‐tetrahydronaphtalene derivatives 1 and 4, clearly underlining the role the sterically demanding group on phosphorus plays in these transformations. The reactivity studies are supported by theoretical studies, demonstrating a thermodynamic preference for the C−H activation products. Additionally, we show that there are potential pitfalls in the synthesis of Cp*2AlH, the precursor to make (Cp*Al)4 and give recommendations how to circumvent these. [ABSTRACT FROM AUTHOR]

Highlights the 75th founding anniversary of the International Council of Nurses. Significance of the role played by Florence Nightingale in the founding of the nursing as a formal medical profession; Philosophy of the nursing profession; Impact of nurses on the development of positive health, planning and research within the community.