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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]

As previously reported, photoisomerization of the open-shell singlet biradicaloid [TerNP]2CNDmp (2) yields its closed-shell housane-type isomer (3). In the present study, pump–probe spectroscopy was applied to investigate the excited-state dynamics of the photoisomerization, indicating ultrafast de-excitation of the S1 state through a conical intersection, in agreement with computational predictions. The structural and electronic changes during the isomerization process are discussed to gain an understanding of the reaction pathway and the transformation of the biradicaloid to a closed-shell species. [ABSTRACT FROM AUTHOR]

The photo-isomerization of an isolable five-membered singlet biradical based on C, N, and P ([TerNP]2CNDmp, 2a) selectively afforded a closed-shell housane-type isomer (3a) by forming a transannular P–P bond. In the dark, the housane-type species re-isomerized to the biradical, resulting in a fully reversible overall process. In the present study, the influence of tBuNC on the thermal reverse reaction was investigated: the isonitrile acted as a catalyst, thus allowing control over the thermal reaction rate. Moreover, tBuNC also reacted with the biradical to form an adduct species ([TerNP]2CNDmp·CNtBu, 4a), which can be regarded as the resting state of the system. The reactive species 2a and 3a could be re-generated in situ by irradiation with red light. The results of this study extend our understanding of this new class of molecular switches. [ABSTRACT FROM AUTHOR]

The trapping of classical hydrogen pseudohalides (HX, X = pseudohalogen = CN, N3, NCO, NCS, and PCO) utilizing a phosphorus-centered cyclic biradicaloid, [P(μ-NTer)]2, is reported. These formal Brønsted acids were generated in situ as gases and passed over the trapping reagent, the biradicaloid [P(μ-NTer)]2, leading to the formation of the addition product [HP(μ-NTer)2PX] (successful for X = CN, N3, and NCO). In addition to this direct addition reaction, a two-step procedure was also applied because we failed in isolating HPCO and HNCS addition products. This two-step process comprises the generation and isolation of the highly reactive [HP(μ-NTer)2PX]+ cation as a [B(C6F5)4]− salt, followed by salt metathesis with salts such as [cat]X (cat = PPh4, n-Bu3NMe), which also gives the desired [HP(μ-NTer)2PX] product, with the exception of the reaction with the PCO− salt. In this case, proton migration was observed, finally affording the formation of a [3.1.1]-hetero-propellane-type cage compound, an OC(H)P isomer of a HPCO adduct. All discussed species were fully characterized. [ABSTRACT FROM AUTHOR]

En 1976, la Ligue s'est dotée de nouveaux Statuts. Il a fallu quatre années d'études, de recherches et de discussions pour qu'une commission spéciale, créée en 1973 par le Conseil des Gouverneurs, aboutisse, avec la participation active des Sociétés nationales, membres de la Ligue, à l'élaboration de ce qui doit être la nouvelle Charte de la Ligue pour les années à venir. [ABSTRACT FROM PUBLISHER]

Cuando se trata de explicar, con términos sencillos, qué es la Cruz Roja, se la define, a menudo, de tres maneras: es un emblema, un símbolo protector o descriptivo de un movimiento; es una organización mundial, integrada por 230 millones de miembros, casi todos voluntarios, agrupados en 126 Sociedades nacionales; es, también, un ideal, en que se inspira una acción tendente a hacer que ese ideal sea realidad y que se base sobre un firme fe en una solidaridad humana global y activa en la lucha contra el sufrimiento.En todas esas definiciones hay un elemento esencialísimo: el ser humano: hombres, mujeres y niños protegidos por el emblema, que participan activamente en la acción de la organización o que creen en su ideal. Por lo tanto, es normal que entre los principios fundamentales de la Cruz Roja haya une frase en la que se declara que la Cruz Roja es una organización voluntaria y desinteresada. [ABSTRACT FROM PUBLISHER]

El señor Jean Pictet, al limite de la edad laboral y tras cuarenta y dos años de actividad al servicio del CICR, se jubilará el 30 dejunio de 1979.La can era del señor Pictet es de plenitud. Comenzó el año 1937 en el CICR, a la vez como pensador, jurista, escritor, profesor y hombre de actión, participando en todas las grandes empresas de la Cruz Roja, de las que ha sido inspirador y guía. [ABSTRACT FROM PUBLISHER]

When trying, in very popular terms, to explain what the Red Cross is, we sometimes define it in three ways: it is an emblem, a symbol, protecting or designating a movement; it is a world organization with 230 million members, almost all of them volunteers, brought together into 126 National Societies; but it is also an ideal, inspiring action to make this ideal a reality, based on a firm belief in a global, human solidarity, active in the fight against suffering. [ABSTRACT FROM PUBLISHER]

On 30 June 1979, Mr. Jean Pictet will reach retirement age after forty-two years of service with the ICRC.He joined the ICRC in 1937 and has had a very full career. He is a thinker, a jurist, a writer, a teacher and at the same time a man of action, who took part in all major Red Cross undertakings; he is the inspirer and the mentor of the Red Cross. [ABSTRACT FROM PUBLISHER]

In 1976 the League adopted a new constitution. Four years of study, research and discussion were necessary until the special commission, set up by the Board of Governors in 1973, with the co-operation of National Societies, came up with what is to be the charter of the League for years to come. [ABSTRACT FROM PUBLISHER]

It comes natural these days to associate the concept of solidarity with the universality of the work of the Red Cross. Serving the same ideal, respecting the same principles, carrying out similar activities, Red Cross Societies are linked to each other and belong, as it were, to a single body, the International Red Cross.The solidarity, born of the very structure of the Red Cross movement, is also a powerful incentive, for it manifests itself in the active co-operation of all Red Cross members for the benefit of the whole. The urge which Red Cross men and Societies have to help each other beyond national boundaries has become so strong over the years that it is not too presumptuous to adopt it as a Red Cross principle. By giving the concept of charity a universal dimension for the benefit of suffering mankind, solidarity is akin to the principles of humanity and universality of which it is both the emanation and the moving force. [ABSTRACT FROM PUBLISHER]

It is a pleasure for me, as Secretary-General of the League of Red Cross Societies, to write an article for the outstanding review produced by the International Committee. It is also a further opportunity to give fresh testimony to the cordial and harmonious co-operation between our two institutions, not that this needs any corroboration. [ABSTRACT FROM PUBLISHER]

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.

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, Ar TerP(PMe 3 ) ( Ar Ter=2,6-Ar 2 -C 6 H 3 ), with (Cp*Al) 4 (Cp*=C 5 (CH 3 ) 5 ) afforded the phosphaalumenes Ar TerPAlCp* as isolable, violet, thermally stable compounds. In here we describe attempts to utilize Mes*P(PMe 3 ) (Mes*=2,4,6-tBu 3 -C 6 H 2 ) as a phosphinidene source in combination with different Al(I) precursors, namely Dip NacnacAl ( Dip Nacnac=HC[C(Me)NDip] 2 , Dip=2,6-iPr 2 -C 6 H 3 ), (Cp*Al) 4 and Cp 3t Al (Cp 3t =1,2,4-tBu 3 -C 5 H 2 ). 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* 2 AlH, the precursor to make (Cp*Al) 4 and give recommendations how to circumvent these., (© 2023 The Authors. ChemPlusChem published by Wiley-VCH GmbH.)