Search

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]

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]

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.)