3,047 research outputs found
Mães perturbadoras, filhos monstruosos: uma leitura de Distância de resgate, de Samanta Schweblin
No full textDistância de resgate (2016) é a primeira e única novela de Samanta Schweblin, escritora argentina tradicionalmente contista. A narrativa se dá através de um diálogo alucinante entre a narradora e seu interlocutor, e tem como tema central a relação ao mesmo tempo delicada e perturbadora entre duas mães e seus respectivos filhos. O presente trabalho é guiado pelo interesse em analisar tais relações, com foco nas tradicionais noções de instinto materno e inocência infantil. Com o intuito de auxiliar no entendimento das temáticas destacadas, propõe-se o estudo de contos selecionados da autora. Tenciona-se, finalmente, discorrer acerca das manifestações do fantástico nos textos citados, considerando-se que a distorção sutil da realidade é um dos traços marcantes da produção de Schweblin.Fever dream (2016) is the first and only novel ever written by Samanta Schweblin, an Argentinian short story writer. The narrative develops itself through a conversation between the narrator and her interlocutor, and focuses mainly on the delicate yet disturbing relationship between two mothers and their children. The present paper is guided by the interest of analyzing these relations, focusing on the traditional concepts of maternal instinct and child innocence. With the intention of helping in the understanding of these themes, a study of selected short stories by the author will be made. Finally, the manifestation of the fantastic genre in the mentioned texts will be studied, considering that the distortion of reality is one of the distinct traits of Schweblins production
Nickela‐electrocatalyzed Mild C−H Alkylations at Room Temperature
No full textAbstract Direct alkylations of carboxylic acid derivatives are challenging and particularly nickel catalysis commonly requires high reaction temperatures and strong bases, translating into limited substrate scope. Herein, nickel‐catalyzed C−H alkylations of unactivated 8‐aminoquinoline amides have been realized under exceedingly mild conditions, namely at room temperature, with a mild base and a user‐friendly electrochemical setup. This electrocatalyzed C−H alkylation displays high functional group tolerance and is applicable to both the primary and secondary alkylation. Based on detailed mechanistic studies, a nickel(II/III/I) catalytic manifold has been proposed.Electrochemically enabled nickel‐catalyzed C−H alkylations with primary and secondary alkyl halides have been accomplished under exceedingly mild reaction conditions with Et3N at room temperature. Detailed mechanistic studies provided support for a nickel(II/III/I) manifold. imageDFG http://dx.doi.org/10.13039/501100001659Alexander von Humboldt-Stiftung http://dx.doi.org/10.13039/10000515
Informetrics on M. N. Srinivas
No full textM. N. Srinivas, the well known sociologist is widely recognised as architect of modern Indian sociology and social anthropology. His publications have been analysed by year, domain, authorship pattern, channels of communication used. Keywords, etc. The results indicate that the papers published by him are of a nature that qualify him to be a 'role model' for the younger generations to emulate.
By the end of 1995, Srinivas had to his credit 144 papers which, included 33 broad papers in sociology and anthropology; 18 papers in social change; 28 papers in village studies; 12 papers on religion; 17 papers on caste and 36 papers of general popular interest. The periods 1958-61 and 1974-77, when Srinivas was 38-41 and 58-61 years old. were his most productive periods with highest publication activity
Remote C–H Functionalizations by Ruthenium Catalysis
No full textAbstract Synthetic transformations of otherwise inert C–H bonds have emerged as a powerful tool for molecular modifications during the last decades, with broad applications towards pharmaceuticals, material sciences, and crop protection. Consistently, a key challenge in C–H activation chemistry is the full control of site-selectivity. In addition to substrate control through steric hindrance or kinetic acidity of C–H bonds, one important approach for the site-selective C–H transformation of arenes is the use of chelation-assistance through directing groups, therefore leading to proximity-induced ortho-C–H metalation. In contrast, more challenging remote C–H activations at the meta- or para-positions continue to be scarce. Within this review, we demonstrate the distinct character of ruthenium catalysis for remote C–H activations until March 2021, highlighting among others late-stage modifications of bio-relevant molecules. Moreover, we discuss important mechanistic insights by experiments and computation, illustrating the key importance of carboxylate-assisted C–H activation with ruthenium(II) complexes. 1 Introduction 2 Stoichiometric Remote C–H Functionalizations 3 meta-C–H Functionalizations 4 para-C–H Functionalizations 5 meta-/ortho-C–H Difunctionalizations 6 Conclusion
Nickel‐Catalyzed Electrooxidative C−H Amination: Support for Nickel(IV)
No full textAbstract Nickel‐catalyzed electrochemical C−H aminations were accomplished by chemo‐ and position‐selective C−H activation with ample scope. Detailed mechanistic studies highlighted a facile C−H cleavage with unique chemo‐selectivity, while cyclovoltammetric analysis provided support for a nickel(II/III/IV) manifold.Distinguished International Students Scholarship https://doi.org/10.13039/501100010893Deutsche Forschungsgemeinschaft https://doi.org/10.13039/501100001659Alexander von Humboldt-Stiftung https://doi.org/10.13039/10000515
Nickelaelektrokatalysierte, milde C‐H‐Alkylierungen bei Raumtemperatur
No full textDFG http://dx.doi.org/10.13039/501100001659Alexander von Humboldt-Stiftung http://dx.doi.org/10.13039/10000515
Evolution of High‐Valent Nickela‐Electrocatalyzed C−H Activation: From Cross(‐Electrophile)‐Couplings to Electrooxidative C−H Transformations
No full textAbstract C−H activation has emerged as one of the most efficient tools for the formation of carbon–carbon and carbon–heteroatom bonds, avoiding the use of prefunctionalized materials. In spite of tremendous progress in the field, stoichiometric quantities of toxic and/or costly chemical redox reagents, such as silver(I) or copper(II) salts, are largely required for oxidative C−H activations. Recently, electrosynthesis has experienced a remarkable renaissance that enables the use of storable, safe and waste‐free electric current as a redox equivalent. While major recent momentum was gained in electrocatalyzed C−H activations by 4d and 5d metals, user‐friendly and inexpensive nickela‐electrocatalysis has until recently proven elusive for oxidative C−H activations. Herein, the early developments of nickela‐electrocatalyzed reductive cross‐electrophile couplings as well as net‐redox‐neutral cross‐couplings are first introduced. The focus of this Minireview is, however, the recent emergence of nickel‐catalyzed electrooxidative C−H activations until April 2020.Go electro! Nickela‐electrocatalyzed C−H activations have emerged as a sustainable platform in molecular sciences that avoid substrate prefunctionalizations and chemical oxidants by electricity. The robust nickela‐electrooxidations enabled C−C, C−O, and C−N formations with ample scope under exceedingly mild conditions. imageAlexander von Humboldt-Stiftung http://dx.doi.org/10.13039/100005156China Scholarship Council http://dx.doi.org/10.13039/501100004543DFG http://dx.doi.org/10.13039/50110000165
Mangana( iii / iv )electro-catalyzed C(sp 3 )–H azidation
No full textThe merger of manganese-catalyzed C–H functionalization with electrosynthesis enabled C(sp 3 )–H azidation devoid of chemical oxidants or photochemical irradiation. Detailed mechanistic studies are supportive of a manganese( iii/iv ) electrocatalysis.Manganaelectro-catalyzed azidation of otherwise inert C(sp 3 )–H bonds was accomplished using most user-friendly sodium azide as the nitrogen-source. The operationally simple, resource-economic C–H azidation strategy was characterized by mild reaction conditions, no directing group, traceless electrons as the sole redox-reagent, Earth-abundant manganese as the catalyst, high functional-group compatibility and high chemoselectivity, setting the stage for late-stage azidation of bioactive compounds. Detailed mechanistic studies by experiment, spectrophotometry and cyclic voltammetry provided strong support for metal-catalyzed aliphatic radical formation, along with subsequent azidyl radical transfer within a manganese( iii / iv ) manifold
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