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The unprecedented liquid–liquid extraction of the dinegative chromate ion (CrO42–) from neutral aqueous solutions into aliphatic hydrocarbon solvents using nanojars as extraction agents is demonstrated. Transferring chromate from water into an organic solvent is extremely challenging due to its large hydration energy (ΔGh° = −950 kJ/mol) and strong oxidizing ability. Owing to their highly hydrophilic anion binding pockets lined by a multitude of hydrogen bond donor OH groups, neutral nanojars of the formula [cis-CuII(μ-OH)(μ-4-Rpz)]n (n = 27–33; pz = pyrazolate anion; R = H or n-octyl) strongly bind the CrO42– ion and efficiently transfer it from water into n-heptane or C11 – C13 isoalkanes (when R = n-octyl). The extracted chromate can easily be recovered from the organic layer by stripping with an aqueous acid solution. Electrospray ionization mass spectrometric, UV–vis and paramagnetic 1H NMR spectroscopic, X-ray crystallographic, and thermal stability studies in solution and chemical stability studies toward NH3, methanol, and Ba2+ ions are employed to explore the binding of the CrO42– ion by nanojars. Titration of carbonate nanojars [CO3 ⊂ {Cu(OH)(pz)}n]2– with H2CrO4 leads to anion exchange and the formation of chromate nanojars [CrO4 ⊂ {Cu(OH)(pz)}n]2–. Details of chromate binding by H-bonding based on single-crystal structures of (Bu4N)2[CrO4 ⊂ {Cu(OH)(pz)}28], four pseudopolymorphs of (Bu4N)2[CrO4 ⊂ {Cu(OH)(pz)}31], and also the methoxy-substituted derivative (Bu4N)2[CrO4 ⊂ {Cu31(OH)30(OCH3)(pz)31}] are presented. 

Abstract Closely related species often use the same genes to adapt to similar environments. However, we know little about why such genes possess increased adaptive potential and whether this is conserved across deeper evolutionary lineages. Adaptation to climate presents a natural laboratory to test these ideas, as even distantly related species must contend with similar stresses. Here, we re-analyse genomic data from thousands of individuals from 25 plant species as diverged as lodgepole pine andArabidopsis(~300 Myr). We test for genetic repeatability based on within-species associations between allele frequencies in genes and variation in 21 climate variables. Our results demonstrate significant statistical evidence for genetic repeatability across deep time that is not expected under randomness, identifying a suite of 108 gene families (orthogroups) and gene functions that repeatedly drive local adaptation to climate. This set includes many orthogroups with well-known functions in abiotic stress response. Using gene co-expression networks to quantify pleiotropy, we find that orthogroups with stronger evidence for repeatability exhibit greater network centrality and broader expression across tissues (higher pleiotropy), contrary to the ‘cost of complexity’ theory. These gene families may be important in helping wild and crop species cope with future climate change, representing important candidates for future study.