21 research outputs found
Новий формат співробітництва (Договір про співробітництво між Національною академією наук України і Національною академією наук Киргизької Республіки)
A one-pot method has been developed for the oxidative cleavage of internal alkenes into aldehydes by using 0.5 mol % of the nonheme iron complex [Fe(OTf)2(mix-bpbp)] (bpbp=N,N′-bis(2-picolyl)-2,2′-bipyrrolidine) as catalyst and 1.5 equivalents of hydrogen peroxide and 1 equivalent of sodium periodate as oxidants. A mixture of diastereomers of the chiral bpbp ligand can be used, thereby omitting the need for resolution of its optically active components. The cleavage reaction can be performed in one pot within 20 h and under ambient conditions. Addition of water after the epoxidation, acidification and subsequent pH neutralization are crucial to perform the epoxidation, hydrolysis, and subsequent diol cleavage in one pot. High aldehyde yields can be obtained for the cleavage of internal aliphatic double bonds with cis and trans configuration (86–98 %) and unsaturated fatty acids and esters (69–96 %). Good aldehyde yields are obtained in reactions of trisubstituted and terminal alkenes (62–63 %). The products can be easily isolated by a simple extraction step with an organic solvent. The presented protocol involves a lower catalyst loading than conventional methods based on Ru or Os. Also, hydrogen peroxide can be used as the oxidant in this case, which is often disproportionated by second- and third-row metals. By using only mild oxidants, overoxidation of the aldehyde to the carboxylic acid is prevented
A metal-free, one-pot method for the oxidative cleavage of internal aliphatic alkenes into carboxylic acids
The oxidative cleavage of terpenes and unsaturated fatty acids into carbonyl compounds is an industrially interesting reaction. We have developed a metal-free protocol that can oxidatively cleave unsaturated fatty acids, terpenes and a variety of other alkenes into carboxylic acids in a synthetically straightforward, one-pot protocol. Near stoichiometric amounts of a combination of oxone and periodate are used in aqueous acetonitrile without additional additives, acids or emulsifiers. The solvent system and the reaction temperature have a profound influence on the reactivity of the substrates; conditions have been optimized for a broad scope of alkenes. The products can be isolated by simple extraction with an organic solvent without additional purification: the carboxylic acids are obtained in high yield (80–96%) as colourless solid or liquid products
A metal-free, one-pot method for the oxidative cleavage of internal aliphatic alkenes into carboxylic acids
The oxidative cleavage of terpenes and unsaturated fatty acids into carbonyl compounds is an industrially interesting reaction. We have developed a metal-free protocol that can oxidatively cleave unsaturated fatty acids, terpenes and a variety of other alkenes into carboxylic acids in a synthetically straightforward, one-pot protocol. Near stoichiometric amounts of a combination of oxone and periodate are used in aqueous acetonitrile without additional additives, acids or emulsifiers. The solvent system and the reaction temperature have a profound influence on the reactivity of the substrates; conditions have been optimized for a broad scope of alkenes. The products can be isolated by simple extraction with an organic solvent without additional purification: the carboxylic acids are obtained in high yield (80–96%) as colourless solid or liquid products
Liquid-phase parahydrogen-induced polarization (phip) with ligand-capped platinum nanoparticles
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A New Ir-NHC Catalyst for Signal Amplification by Reversible Exchange in D2O
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159857.pdf (publisher's version ) (Closed access
Direct hyperpolarization of nitrogen-15 in aqueous media with parahydrogen in reversible exchange
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175417.pdf (Publisher’s version ) (Open Access
Unearthing withling(s):children, tweezers, and worms and the emergence of joy and suffering in a kindergarten yard
Abstract
While there have been several attempts to account for relationships between humans and nonhuman animals in the social sciences and humanities, the discipline of education has, until recently, steered clear from the so-called animal turn. Drawing on post-anthropocentric theorizations, we introduce a concept of withling(s) and develop it empirically in the context of early years education. In particular, we zoom into one practice of science education at a kindergarten in order to consider what kind of child-animal relations are and might become invoked. Our concept of withling(s) is not an a priori positive relatings, as during the dance between earthworms, pupils, teachers, and technologies, both joy and suffering are invoked simultaneously
What Leads Young People to Identify with Europe? An Exploration of the Impact of Exposure to Europe and Political Engagement on European Identity among Young Europeans
Ecocentric education
Ecocentrism has roots in environmental philosophy, which questions the conceptual dichotomy between humans and the environment, acknowledging nonhuman species' right to flourish independently of human interest (Naess 1973). Generally, ecocentrism refers to a planet- and nature-centered as opposed to the human-centered (anthropocentric) system of values. Inspired by this philosophy, ecocentric education focuses on intrinsic values of the ecosystem, environment, and individual living beings and habitats in environmental education (EE) and education for sustainable development (ESD).
https://rd.springer.com/referencework/10.1007/978-3-319-63951-2
LinkedIn: https://www.linkedin.com/in/helenkopnina