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Abstract The Alu Yb-lineage is a 'young' primarily human-specific group of short interspersed element (SINE) subfamilies that have integrated throughout the human genome. In this study, we have computationally screened the draft sequence of the human genome for Alu Yb-lineage subfamily members present on autosomal chromosomes. A total of 1,733 Yb Alu subfamily members have integrated into human autosomes. The average ages of Yb-lineage subfamilies, Yb7, Yb8 and Yb9, are estimated as 4.81, 2.39 and 2.32 million years, respectively. In order to determine the contribution of the Alu Yb-lineage to human genomic diversity, 1,202 loci were analysed using polymerase chain reaction (PCR)-based assays, which amplify the genomic regions containing individual Yb-lineage subfamily members. Approximately 20 per cent of the Yb-lineage Alu elements are polymorphic for insertion presence/absence in the human genome. Fewer than 0.5 per cent of the Yb loci also demonstrate insertions at orthologous positions in non-human primate genomes. Genomic sequencing of these unusual loci demonstrates that each of the orthologous loci from non-human primate genomes contains older Y, Sg and Sx Alu family members that have been altered, through various mechanisms, into Yb8 sequences. These data suggest that Alu Yb-lineage subfamily members are largely restricted to the human genome. The high copy number, level of insertion polymorphism and estimated age indicate that members of the Alu Yb elements will be useful in a wide range of genetic analyses.

Fully earth‐abundant and highly efficient systems for producing syngas CO/H2 through photocatalytic reduction from CO2 are essential to approach a sustainable way of closing the carbon cycle. Herein, the synthesis and characterization of a new iron complex, FeIIL(NCS)2py, coordinated to an N,N,N‐pincer ligand 2,6‐bis(4'‐phenyl‐1',2',3'‐triazol‐1'‐yl‐methyl)pyridine (L), two isothiocyanate groups (NCS) and one pyridine is reported. Its catalytic activity in the photo‐driven reduction of carbon dioxide has been investigated and compared with its CoII analogue (CoL(NCS)2py) and their homoleptic complexes ML2. In this work, the catalysts are used in combination with the heteroleptic complex [CuI(dmp)(DPEphos)], where dmp is 2,9‐dimethyl‐1,10‐phenanthroline and DPEPhos is bis[(2‐diphenylphosphino)phenyl] ether, to reach entirely earth‐abundant systems. The new iron heteroleptic complex FeIIL(NCS)2py showed considerable activity with a TONCO of 576 obtained after 4 h (TOF=144 h−1) through visible light (λ=420 nm) and a quantum yield of 7.1 %. [ABSTRACT FROM AUTHOR]

We have added the {ReIVX5}− (X=Br, Cl) synthon to a pocket‐based ligand to provide supramolecular design using halogen⋅⋅⋅halogen interactions within an FeIII system that has the potential to undergo spin crossover (SCO). By removing the solvent from the crystal lattice, we "switch on" halogen⋅⋅⋅halogen interactions between neighboring molecules, providing a supramolecular cooperative pathway for SCO. Furthermore, changes to the halogen‐based interaction allow us to modify the temperature and nature of the SCO event. [ABSTRACT FROM AUTHOR]

We present the synthesis, magnetic and photophysical properties of four mononuclear LnIII complexes in two isostructural lattices containing GdIII and ErIII. A heptadentate Schiff base ligand and acetate versus trifluoroacetate were used to synthesise complexes 1–4, among which the two ErIII complexes 2 and 4 exhibit field-induced SIM behaviour with almost similar Ueff values (31.6 K for 2 and 32.7 K for 4). Ab initio calculations show the structure of the low-lying energy states and highlight that there is already significant tunnelling in the ground doublet state, but the application of a weak magnetic field of 0.05 T is sufficient for ac magnetic measurements to suppress tunnelling in the ground state. The calculated main magnetic axes (gZ) of the ground Kramers doublets show small differences between the two ErIII compounds 2 and 4 due to their different ligand fields. [ABSTRACT FROM AUTHOR]

Dipyrromethene metal complexes are fascinating molecules that have applications as light‐harvesting systems, luminophores, and laser dyes. Recently, it has been shown that structurally rigid bis(dipyrrinato) zinc(II) complexes exhibit high fluorescence with comparable quantum yields to those of boron dipyrromethenes or BODIPYs. Herein, eight new bis(dipyrrinato) ZnII complexes, obtained from symmetric and unsymmetrical functionalization of the dipyrromethene structure through a Knoevenagel reaction, are reported. It was possible not only to vary the maximum visible absorption from 490 to 630 nm, but also to enhance the emission quantum yield up to 66 %, which is extraordinarily high for homoleptic bis(dipyrrinato) zinc complexes. These results pave the way for designing highly luminescent bis(dipyrrinato) zinc complexes. New bis(dipyrrinato) Zn(II) complexes, obtained from symmetric and unsymmetrical functionalization of the dipyrromethene structure through a Knoevenagel reaction, are reported. It was possible not only to vary the maximum visible absorption from 490 to 630 nm, but also to enhance the emission quantum yield up to 66 %, which is extraordinarily high for homoleptic bis(dipyrrinato) zinc complexes. These results pave the way for designing highly luminescent bis(dipyrrinato) zinc complexes. [ABSTRACT FROM AUTHOR]

Structural, magnetic, and spectroscopic data on a Mn 3+ spin-crossover complex with Schiff base ligand 4-OMe-Sal 2 323, isolated in crystal lattices with five different counteranions, are reported. Complexes of [Mn(4-OMe-Sal 2 323)]X where X = ClO 4 - ( 1 ), BF 4 - ( 2 ), NO 3 - ( 3 ), Br - ( 4 ), and I - ( 5 ) crystallize isotypically in the chiral orthorhombic space group P 2 1 2 1 2 with a range of spin state preferences for the [Mn(4-OMe-Sal 2 323)] + complex cation over the temperature range 5-300 K. Complexes 1 and 2 are high-spin, complex 4 undergoes a gradual and complete thermal spin crossover, while complexes 3 and 5 show stepped crossovers with different ratios of spin triplet and quintet forms in the intermediate temperature range. High-field electron paramagnetic resonance was used to measure the zero-field splitting parameters associated with the spin triplet and quintet states at temperatures below 10 K for complexes 4 and 2 with respective values: D S =1 = +23.38(1) cm -1 , E S =1 = +2.79(1) cm -1 , and D S =2 = +6.9(3) cm -1 , with a distribution of E parameters for the S = 2 state. Solid-state circular dichroism (CD) spectra on high-spin complex 1 at room temperature reveal a 2:1 ratio of enantiomers in the chiral conglomerate, and solution CD measurements on the same sample in methanol show that it is stable toward racemization. Solid-state UV-vis absorption spectra on high-spin complex 1 and mixed S = 1/ S = 2 sample 5 reveal different intensities at higher energies, in line with the different electronic composition. The statistical prevalence of homochiral crystallization of [Mn(4-OMe-Sal 2 323)] + in five lattices with different achiral counterions suggests that the chirality may be directed by the 4-OMe-Sal 2 323 ligand.

The first dinuclear and trinuclear chromium(III) and dinuclear vanadium(III) complexes of N 4 - R -substituted-3,5-di(2-pyridyl)-1,2,4-triazole ( Rdpt ) ligands have been prepared by solvothermal complexations under inert atmospheres, and characterized. The reactions of Cr III and V III with adpt ( R = amino) resulted in deamination of the ligand and yielded the dinuclear doubly-triazolate bridged complexes [ V 2 III ( dpt - ) 2 Cl 4 ] ( 1 ) and [ Cr 2 III ( dpt - ) 2 Cl 4 ] ( 2 ). In the case of the Cr III complex 2 this bridging results in a rare example of ferromagnetic coupling for a dinuclear Cr III compound. DFT studies confirm that in 2 the ferromagnetic coupling pathways dominate over the antiferromagnetic pathways, whereas in 1 the reverse occurs, consistent with the observed overall antiferromagnetic coupling in that case. It was also found that the use of different additives in the reaction allows the nuclearity of the Cr III product to be manipulated, giving either the dinuclear system, or the first example of a trinuclear circular helicate for a Rdpt complex, [ Cr 3 III ( dpt ) 3 Cl 6 ]·1¾MeCN·¼DCM ( 3 ). Reaction of N 4 - pydpt (R = 4-pyridyl) with V III led to an unusual shift of the pyridyl substituent from N 4 to N 1 of the triazole, forming the ligand isomer N 1 - pydpt , and giving a dinuclear doubly-triazole bridged complex, [ V 2 III ( N 1 - pydpt ) 2 Cl 6 ]·2MeCN ( 4 ). Reaction with Cr III results in loss of the 4-pyridyl ring and a mixture of the di- and trinuclear complexes, 2 and 3 . Interestingly, partial oxidation of the V III in dinuclear complex 4 to vanadyl V IV =O was identified by crystallographic analysis of partially oxidized single crystals, [(V IV O) 0.84 (V III ) 1.16 ( N 1 - pydpt ) 2 Cl 5.16 ]·0.84H 2 O·1.16MeCN ( 5 )., (Copyright © 2020 Rinck, Kitchen, Carter, Lan, Anson, Fink, Brooker and Powell.)

Two monolanthanide-containing polyanions based on monolacunary Keggin germanotungstates [Ln(H 2 O) n GeW 11 O 39 ] 5- (Ln = Dy, Er, n = 4,3) have been synthesized in simple one-pot synthetic procedure and compositionally characterized in solid state by single-crystal X-ray diffraction, powder X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, and elemental analysis. Electronic absorption and emission spectra of the title compounds in solution were also studied. The [Dy III (H 2 O) 4 GeW 11 O 39 ] 5- Keggin POM exhibits a slow relaxation of magnetization. The cyclic voltammetry measurements and mass spectrometry were carried out to check the stability of the compounds in solution. Both polyanions prove efficient in the electrocatalytic reduction of nitrite. To our knowledge, this observation establishes the first example of electrocatalysis of nitrite reduction by all inorganic monolanthanide-containing germanotungstates family., Competing Interests: The authors declare no competing financial interest., (Copyright © 2019 American Chemical Society.)