55 research outputs found

    Group 11 tris(pyrazolyl)methane complexes: structural features and catalytic applications

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    Tris(pyrazolyl)methane ligands (Tpmx) have been for years a step behind their highly popular boron-anionic analogues, the tris(pyrazolyl)borate ligands (Tpx). However, in the last decade the development of new members of this family of ligands has boosted a number of contributions albeit their use in coordination chemistry. This fact has also triggered the application of metal-Tpmx complexes as catalysts for a range of organic transformations, particularly with group 11 metals. The main structural features of complexes containing the TpmxM (M = Cu, Ag, Au) unit and their success as catalysts in a variety of reactions under homogeneous or heterogeneous conditions are presented.We thank MINECO for support with Grant CTQ2017-82893-C2-1-

    The quantitative genetic basis of inducible defences and life-history plasticity in Daphnia pulex

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    Functionalised tris(pyrazolyl)methane ligands and Re(CO)3 complexes thereof

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    The synthesis of new tripodal nitrogen ligands derived from tris(pyrazolyl)methane (TpmR, R = H, tBu, Ph in 3-position) is described. After deprotonation of the parent tris(pyrazolyl)methane TpmR, the carbanion reacts readily with ethylene oxide to yield the 3,3,3-tris(3-substituted pyrazolyl)propanol ligands[(3-Rpz)3CCH2CH2OH, R = H, tBu, Ph, 1a-c]. These ligands can be easily derivatised at the alcohol function. Microwave-assisted reactions of these ligands and [Re(CO)5Br] yields the complex [(1a)Re(CO)3]Br (4) in the case of ligand 1a, whereas in the case of the substituted ligands 1b and 1c degradation was observed. The degradation products are identified as [(HpzR)2Re(CO)3Br] [R = tBu (7b), Ph (7c)]. These complexes were also prepared directly from [Re(CO)5Br] and the corresponding pyrazoles by microwave-assisted synthesis. The Re(CO)3 complexes 4 and [(1a)Re(CO)3]OTf (5) are water-soluble. The structures of 5·H2O and [{(pz)3CCH2CH3}Re(CO)3]OTf·1.5H2O·1/2CH3CN (6·1.5H2O·1/2CH3CN) as well as the structure of 7b have been elucidated by X-ray crystallography

    Les autorités bruxelloises

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    Phenotypic plasticity is the ability of an individual genotype to alter aspects of its phenotype depending on the current environment. It is central to the persistence, resistance and resilience of populations facing variation in physical or biological factors. Genetic variation in plasticity is pervasive, which suggests its local adaptation is plausible. Existing studies on the adaptation of plasticity typically focus on single traits and a few populations, while theory about interactions among genes (for example, pleiotropy) suggests that a multi-trait, landscape scale (for example, multiple populations) perspective is required. We present data from a landscape scale, replicated, multi-trait experiment using a classic predator–prey system centred on the water flea Daphnia pulex. We find predator regime-driven differences in genetic variation of multivariate plasticity. These differences are associated with strong divergent selection linked to a predation regime. Our findings are evidence for local adaptation of plasticity, suggesting that responses of populations to environmental variation depend on the conditions in which they evolved in the past

    Trat data of Daphnia pulex

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    Trait data for individual Daphnia pulex from either fish cue- or mideg cue treatment. Below follows a description of the column labels: CLONE - the maternal clone; POND - the pond from which the clone was collected; CUE TREATMENT - the predator cue added to the water; AGE MATURITY - age at maturity (days); SIZE MATURITY - the size at maturity (mm), ADULT GROWTH RATE - the increase in size as adults (day-1); R - the reproductive fitness calculated from the life tabl

    PhenotypicData

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    Phenotypic data used in G-matrix analyses and QST-FST analyse
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