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El uso del agua en las poblaciones de México para las actividades domésticas, de traspatio y agropecuarias demanda formas modernas de gobierno según las circunstancias de cada una. Por ello, en este estudio se analiza a los asentamientos de Yashanal y Tzajalchen, en el municipio de Tenejapa, Chiapas, respecto a su gestión del recurso procedente del manantial situado en el territorio de Yashana, sagrado para los antepasados mayas y de aprovechamiento comunitario actual, concretada con acuerdos que resulten en una estructura viable para los beneficiarios. Según se nota, las diferencias bloquean la distribución del elemento. Se trata al agua como bien público mediante los conceptos de gobernanza, gobernanza comunitaria, actores y gestión, comparando cómo se le gestiona en los dos asentamientos para evaluar la eficiencia en el establecimiento de normas. Se analizan las pugnas entre localidades, observando el comportamiento de los actores públicos y privados, para quienes decidir se complica debido a que no han establecido reglas de interacción por cambios culturales y organizacionales.

La economía chiapaneca enfrenta una crisis de carácter estructural, por lo que en este trabajo se analiza su desempeño con una visión de largo plazo (1900-2015). Aún no hay investigaciones acerca de las causas de su bajo crecimiento, el cual la ha rezagado del promedio nacional y la mantiene como la entidad federativa con los niveles de pobreza más altos y flujos crecientes de migración hacia Estados Unidos de América. La producción de estudios referentes al tema y los resultados regionales del cambio de estrategia nacional al respecto desde 1982 es nula. Por eso esta investigación trata tales efectos. Cabe destacar la carencia de una base analítica sustentada en la política económica predominante en México y su marca en territorios empobrecidos en un contexto dominado por tendencias globales que alteran de muchas formas a las regiones de los países.

En el contexto del dinamismo y contradicciones del sector agroalimentario, en la actualidad los pequeños productores son impulsados a emprender una reestructuración de sus prácticas productivas, a través de la plantación de cultivos orientados a biocombustibles, como el de la palma africana. En este artículo se analizan los procesos de reestructuración productiva, promovida por corpora-ciones de distinto origen y por el Estado, y las acciones realizadas por pequeños productores en un municipio con alta marginación, localizado en una región agroexportadora de Chiapas. Se revisan las contradicciones sociales y ambientales de este cambio y sus implicaciones a futuro, en términos del desarrollo agrícola y alimentario nacional. La expansión de este cultivo acentúa las desigualdades sociales, degrada los recursos naturales, utiliza mucha energía fósil, impulsa la concentración de la tierra, debilita los sistemas locales de provisión de alimentos y reduce los márgenes del valor generado en la cadena agroalimentaria para los pequeños productores.

El presente ensayo busca explicar cómo la construcción de la relación entre las elites que forman parte del Estado y los grupos sociales que son dirigidos y dominados por el propio Estado —en términos de Gramsci la relación Estado y sociedad civil— generan un tipo de proyecto nacional que impacta al conjunto de territorios, que desde nuestra perspectiva operan como un sistema territorial que compone a un Estado nación. Las condiciones de desarrollo de cada territorio y del conjunto del sistema están afectadas por cómo se estructuran las relaciones entre los grupos de poder local y los grupos de poder central del Estado. Con estas herramientas analíticas se construye una explicación de la relación histórica que se va erigiendo en el México posrevolucionario entre ambos poderes que afecta al desarrollo territorial. ABSTRACT Based upon a gramscian perspective, this paper seeks to explain how the relationship between the State and civil society generates a type of national project that impacts all its territories. Refering to mexican postrevolutionary experience, it is pointed out that development conditions in each territory and in the entire system are affected by the structure of interactions between the local power groups and the State's central power groups.

The major source of fluoride, namely calcium difluoride (CaF 2 ), is derived from the mineral fluorspar. Recent advances in the activation of CaF 2 via mechanochemical methods have inspired investigation of the fundamental properties of Ca-F bonds in molecular complexes. However, the paucity of well-defined molecular Ca-F-containing complexes undermines systematic understanding of the factors governing nucleophilic fluoride delivery. Here we report the use of a multidentate bis(phenoxide) ligand based on a 1,4,7-triazacyclononane (TACN) scaffold for the formation of well-defined Ca-F complexes and demonstrate their capabilities in fluoride delivery. Key to this synthesis is a desymmetrization step carried out on the TACN ligand within the Ca coordination sphere. A series of stable anionic dinuclear calcium fluoride complexes has then been accessed and characterized by NMR spectroscopy (critically by 19 F NMR) and X-ray crystallography. Nucleophilic fluoride delivery can be used to generate C-F, Si-F and S-F bonds, with a notable advance over amide-derived ligand scaffolds being the reduced extent of side reactions derived from competing attack on the electrophile by the less nucleophilic O-donor anionic ligand set., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

An asymmetric 1,2-dicarbofunctionalization of unactivated alkenes with aryl iodides and aryl/alkenylboronic esters under nickel/bioxazoline catalysis is disclosed. A wide array of aryl and alkenyl nucleophiles are tolerated, furnishing the products in good yield and with high enantioselectivity. In addition to terminal alkenes, 1,2-disubstituted internal alkenes participate in the reaction, establishing two contiguous stereocenters with high diastereoselectivity and moderate enantioselectivity. A combination of experimental and computational techniques shed light on the mechanism of the catalytic transformation, pointing to a closed-shell pathway with an enantiodetermining migratory insertion step, where stereoinduction arises from synergistic interactions between the sterically bulky achiral sulfonamide directing group and the hemilabile bidentate ligand.

A nickel-catalyzed 1,2-diarylation of alkenyl ketones with aryl iodides and arylboronic esters is reported. Ketones with a variety of substituents serve as effective directing groups, offering high levels of regiocontrol. A representative product is diversified into a wide range of useful products that are not readily accessible via existing 1,2-diarylation reactions. Preliminary mechanistic studies shed light on the binding mode of the substrate, and Hammett analysis reveals the effect of electronic factors on initial rates.

We report a full account of our research on nickel-catalyzed Markovnikov-selective hydroarylation and hydroalkenylation of non-conjugated alkenes, which has yielded a toolkit of methods that proceed under mild conditions with alkenyl sulfonamide, ketone, and amide substrates. Regioselectivity is controlled through catalyst coordination to the native Lewis basic functional groups contained within these substrates. To maximize product yield, reaction conditions were fine-tuned for each substrate class, reflecting the different coordination properties of the directing functionality. Detailed kinetic and computational studies shed light on the mechanism of this family of transformations, pointing to transmetalation as the turnover-limiting step., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Selective carbon-carbon (C-C) bond formation in chemical synthesis generally requires prefunctionalized building blocks. However, the requisite prefunctionalization steps undermine the overall efficiency of synthetic sequences that rely on such reactions, which is particularly problematic in large-scale applications, such as in the commercial production of pharmaceuticals. Herein, we describe a selective and catalytic method for synthesizing 1,3-enynes without prefunctionalized building blocks. In this transformation several classes of unactivated internal acceptor alkynes can be coupled with terminal donor alkynes to deliver 1,3-enynes in a highly regio- and stereoselective manner. The scope of compatible acceptor alkynes includes propargyl alcohols, (homo)propargyl amine derivatives, and (homo)propargyl carboxamides. This method is facilitated by a tailored P,N-ligand that enables regioselective addition and suppresses secondary E / Z -isomerization of the product. The reaction is scalable and can operate effectively with as low as 0.5 mol % catalyst loading. The products are versatile intermediates that can participate in various downstream transformations. We also present preliminary mechanistic experiments that are consistent with a redox-neutral Pd(II) catalytic cycle.

We report that Ni(COD)(DQ) (COD=1,5-cyclooctadiene, DQ=duroquinone), an air-stable 18-electron complex originally described by Schrauzer in 1962, is a competent precatalyst for a variety of nickel-catalyzed synthetic methods from the literature. Due to its apparent stability, use of Ni(COD)(DQ) as a precatalyst allows reactions to be conveniently performed without use of an inert-atmosphere glovebox, as demonstrated across several case studies., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Nickel-catalyzed three-component alkene difunctionalization has rapidly emerged as a powerful tool for forging two C-C bonds in a single reaction. Building upon the powerful modes of bond construction in traditional two-component cross-coupling, various research groups have demonstrated the versatility of nickel in enabling catalytic 1,2-dicarbofunctionalization using a wide range of carbon-based electrophiles and nucleophiles and in a fully intermolecular fashion. Though this area has emerged only recently, the last few years have witnessed a proliferation of publications on this topic, underscoring the potential of this strategy to develop into a general platform that offers high regio- and stereoselectivity. This minireview highlights the recent progress in the area of intermolecular 1,2-dicarbofunctionalization of alkenes via nickel catalysis and discusses lingering challenges within this reactivity paradigm., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

A palladium(II)-catalyzed enantioselective α-alkylation of azlactones with nonconjugated alkenes is described. The reaction employs a chiral BINOL-derived phosphoric acid as the source of stereoinduction, and a cleavable bidentate directing group appended to the alkene to control the regioselectivity and stabilize the nucleopalladated alkylpalladium(II) intermediate in the catalytic cycle. A wide range of azlactones were found to be compatible under the optimal reaction conditions to afford products bearing α,α-disubstituted α-amino-acid derivatives with high yields and high enantioselectivity., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)