A Theoretical Perspective on the Reactivity of High-valent Mn-Oxo/Nitrene Species Towards Oxidative Transformations

There is a large interest in developing oxidative transformations catalyzed by palladium complexes that employ environmentally friendly and economical oxidizing reagents such as dioxygen. Recently, we have reported the isolation and characterization of various mononuclear PdIII and PdIV complexes supported by the tetradentate ligands N,N’-di-alkyl-butyl-2,11-diaza[3.3](2,6)pyridinophane (RN4, R = tBu, iPr, Me), and the aerobically-induced C-C and C-heteroatom bond formation reactivity was investigated in detail. Given that the steric and electronic properties of the multidentate ligands were shown to tune the stability and reactivity of the corresponding high-valent Pd complexes, herein we report the use of an asymmetric N4 ligand, N-mehtyl-N’-tosyl-2,11-diaza[3.3](2,6)pyridinophane (TsMeN4), in which one amine N atom contains a tosyl group. The N-Ts donor atom exhibits a markedly reduced donating ability, which led to the formation of transiently stable PdIII and PdIV complexes, and consequently the corresponding O2 oxidation reactivity and the subsequent C-C bond formation was improved significantly.

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Improved Oxidative C-C Bond Formation Reactivity of High-Valent Pd Complexes Supported by a Pseudo-Tridentate Ligand

10.26434/chemrxiv.12480311 ◽

2020 ◽

Author(s):

Jason W. Schultz ◽

Nigam P. Rath ◽

Liviu M. Mirica

Keyword(s):

Bond Formation ◽

Palladium Complexes ◽

Tridentate Ligand ◽

Isolation And Characterization ◽

Oxidation Reactivity ◽

Tosyl Group ◽

Oxidative Transformations ◽

Pd Complexes ◽

High Valent ◽

The Stability

There is a large interest in developing oxidative transformations catalyzed by palladium complexes that employ environmentally friendly and economical oxidizing reagents such as dioxygen. Recently, we have reported the isolation and characterization of various mononuclear PdIII and PdIV complexes supported by the tetradentate ligands N,N’-di-alkyl-butyl-2,11-diaza[3.3](2,6)pyridinophane (RN4, R = tBu, iPr, Me), and the aerobically-induced C-C and C-heteroatom bond formation reactivity was investigated in detail. Given that the steric and electronic properties of the multidentate ligands were shown to tune the stability and reactivity of the corresponding high-valent Pd complexes, herein we report the use of an asymmetric N4 ligand, N-mehtyl-N’-tosyl-2,11-diaza[3.3](2,6)pyridinophane (TsMeN4), in which one amine N atom contains a tosyl group. The N-Ts donor atom exhibits a markedly reduced donating ability, which led to the formation of transiently stable PdIII and PdIV complexes, and consequently the corresponding O2 oxidation reactivity and the subsequent C-C bond formation was improved significantly.

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The role of nursing in the rehabilitation of acute stroke patients: Toward a unified theoretical perspective

Pflege ◽

10.1024/1012-5302.12.1.21 ◽

1999 ◽

Vol 12 (1) ◽

pp. 21-27

Author(s):

Marit Kirkevold

Keyword(s):

Acute Stroke ◽

Theoretical Perspective ◽

Stroke Patients ◽

Role Of Nursing ◽

Rolle Der Pflegenden

Eine Übersicht der bestehenden Literatur weist auf Unsicherheiten bezüglich der spezifischen Rolle der Pflegenden in der Rehabilitation von Hirnschlagpatientinnen und -patienten hin. Es existieren zwei unterschiedliche Begrifflichkeiten für die Rolle der Pflegenden, keine davon bezieht sich auf spezifische Rehabilitationsziele oder Patientenergebnisse. Ein anfänglicher theoretischer Beitrag der Rolle der Pflege in der Genesung vom Hirnschlag wird als Struktur unterbreitet, um die therapeutischen Aspekte der Pflege im Koordinieren, Erhalten und Üben zu vereinen. Bestehende Literatur untermauert diesen Beitrag. Weitere Forschung ist jedoch notwendig, um den spezifischen Inhalt und Fokus der Pflege in der Genesung bei Hirnschlag zu entwickeln.

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