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The NUCLEUS experiment aims to perform a high-precision measurement of Coherent Elastic Neutrino-Nucleus Scattering (CEvNS) at the EdF Chooz B nuclear power plant in France. CEvNS is a unique process to study neutrino properties and to search for physics beyond the Standard Model. The study of CEvNS is also important for light Dark-Matter searches. It could be a possible irreducible background for high-sensitivity Dark-Matter experiments. NUCLEUS is an experiment under construction based on ultra-low threshold ($\sim$20 eV$_{nr}$) cryogenic calorimeters, operated at tens-of-mK temperatures.

The new complex of Zn(II) with 4-ammino-2,2,6,6- tetramethylpiperidine, [C9H22N2]ZnCl4, has been prepared and characterized by various physicochemical studies. This compound crystallizes in the monoclinic system, with the space group P21/c and the following cell parameters: a = 9.8682(7), b = 7.5164(5), c = 21.019(2) Å, β = 99.003 (7)°, V = 1539.8(2) Å3 and Z = 4. The crystal structure was solved and refined to R = 0.024 using 3070 reflections. The atomic arrangement can be described by slightly distorted tetrahedral ZnCl4 2- anions and 4-ammmonio-2,2,6,6- tetramethylpiperidinium cations holding together by different interactions. The four chlorine atoms of the ZnCl4 2- tetrahedron are acting as acceptors of hydrogen bonds. The crystal packing is influenced by cation-to-anion N-H…Cl and C-H…Cl hydrogen bonds leading to open framework architecture. [ABSTRACT FROM AUTHOR]

In the first part of this work, we have studied the reactivity of an ethanolic solution of diphenylthiocarbazone (C13H12N4S) with an aqueous solution of vanadium(V), leading to a new compound C17H12S (L). This compound was crystallographically characterized and identified by XRD. This technique reveals no metal in the structure. Then, we reacted L with the same metal, producing a dimeric complex V2O4(L)2(H2O)2(OH)2 (C1), characterized by elemental analysis, IR, UV-Visible, 1H NMR, 13C NMR, and 51V NMR spectra. A probable structure has been proposed. [ABSTRACT FROM AUTHOR]

A novel mixed cadmium zirconium cesium oxalate with an open architecture has been synthesized from precipitation methods at room pressure. It crystallizes with an hexagonal symmetry, space group P3112 (no. 151), a=9.105(5) Å, c=23.656(5) Å, V=1698(1) Å3 and Z=3. The structure displays a [CdZr(C2O4)4]2- helicoidal framework built from CdO8 and ZrO8 square-based antiprisms connected through bichelating oxalates, which generates channels along different directions. Cesium cations, hydronium ions and water molecules are located inside the voids of the anionic framework. They exhibit a dynamic disorder which has been further investigated by 1H and 133Cs solid-state NMR. Moreover a phase transition depending both upon ambient temperature and water vapor pressure was evidenced for the title compound. The thermal decomposition has been studied in situ by temperature-dependent X-ray diffraction and thermogravimetry. The final product is a mixture of cadmium oxide, zirconium oxide and cesium carbonate. [Copyright &y& Elsevier]

A novel Ta/Os heterobimetallic complex, [Ta(CH 2 t Bu) 3 (μ-H) 3 OsCp*], 2, is prepared by protonolysis of Ta(CH t Bu)(CH 2 t Bu) 3 with Cp*OsH 5 . Treatment of 2 and its iridium analogue [Ta(CH 2 t Bu) 3 (μ-H) 2 IrCp*], 1, with CO 2 under mild conditions reveal the efficient cleavage of CO 2 , driven by the formation of a tantalum oxo species in conjunction with CO transfer to the osmium or iridium fragments, to form Cp*Ir(CO)H 2 and Cp*Os(CO)H 3 , respectively. This bimetallic reactivity diverges from more classical CO 2 insertion into metal-X (X = metal, hydride, alkyl) bonds.

A salt metathesis synthetic strategy is used to access rare tantalum/coinage metal (Cu, Ag, Au) heterobimetallic complexes. Specifically, complex [Li(THF) 2 ][Ta(C t Bu)(CH 2 t Bu) 3 ], 1 , reacts with (IPr)MCl (M = Cu, Ag, Au, IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) to afford the alkylidyne-bridged species [Ta(CH 2 t Bu) 3 (μ-C t Bu)M(IPr)] 2-M . Interestingly, π-bonding of group 11 metals to the Ta─C moiety promotes a rare alkylidyne alkyl to bis-alkylidene tautomerism, in which compounds 2-M are in equilibrium with [Ta(CH t Bu)(CH 2 t Bu) 2 (μ-CH t Bu)M(IPr)] 3-M . This equilibrium was studied in detail using NMR spectroscopy and computational studies. This reveals that the equilibrium position is strongly dependent on the nature of the coinage metal going down the group 11 triad, thus offering a new valuable avenue for controlling this phenomenon. Furthermore, we show that these uncommon bimetallic couples could open attractive opportunities for synergistic reactivity. We notably report an uncommon deoxygenative carbyne transfer to CO 2 resulting in rare examples of coinage metal ketenyl species, ( t BuCCO)M(IPr), 4-M (M = Cu, Ag, Au). In the case of the Ta/Li analogue 1 , the bis(alkylidene) tautomer is not detected, and the reaction with CO 2 does not cleanly yield ketenyl species, which highlights the pivotal role played by the coinage metal partner in controlling these unconventional reactions.

This work investigates the electron-donating capabilities of two 10-π electron nitrogen bridgehead bicyclic [5,6]-fused ring systems, imidazo[1,2- a ]pyridine and imidazo[1,5- a ]pyridine rings. Eight compounds with varying positions of electron-withdrawing moieties (TCF or DCI) coupled to the imidazopyridine ring were synthesized and studied. DCI-containing compounds ( Ib - IVb ) exhibited a purely dipolar nature with broad absorption bands, weak fluorescence, large Stokes shifts, and strong solvatochromism. In contrast, TCF-containing compounds ( Ia - IVa ) demonstrated diverse properties. Imidazo[1,2- a ]pyridine derivatives Ia and IIa were purely dipolar, while imidazo[1,5- a ]pyridine derivatives IIIa and IVa displayed a cyanine-like character with intense absorption and higher quantum yields of emission. The observed gradual red shift in optical properties with changing electron-donor groups ( IIb < Ib < IIIb < IVb ) and ( IIa < Ia < IIIa < IVa ) underscores the stronger electron-donor character of imidazo[1,5- a ]pyridine compared to that of imidazo[1,2- a ]pyridine. Furthermore, crystalline powders of imidazo[1,2- a ]pyridine derivatives exhibited fluorescence despite minimal emission in solution. Two compounds ( Ib and IVa ) were successfully formulated into nanoparticles for potential in vivo imaging applications in zebrafish embryos.

Dinuclear transition metal complexes with direct metal-metal interactions have the potential to generate unique reactivities and properties. Using asymmetric triazine ligands HN 3 t BuR (R = Et, i Pr, n Bu) featuring different alkyl substituents at 1,3-N centers, we report here the first rational synthesis of 'tetragonal lantern' type Fe(II) triazenides [Fe 2 (N 3 t BuR) 4 ] [R = Et (1), i Pr (2), n Bu (3)] having an exceptionally short Fe-Fe distance (2.167-2.174 Å). Unlike the previously reported lantern structures with related amidinate or guanidinate ligands, highly air-sensitive 1-3 show a lower spin ground state, as indicated by Mössbauer, 1 H NMR and DFT studies.

Porphyrin based Metal-Organic Frameworks (MOFs) have generated high interest because of their unique combination of light absorption, electron transfer and guest adsorption/desorption properties. In this study, we expand the range of available MOF materials by focusing on the seldom studied porphyrin ligand H 10 TcatPP, functionalized with tetracatecholate coordinating groups. A systematic evaluation of its reactivity with M(iii) cations (Al, Fe, and In) led to the synthesis and isolation of three novel MOF phases. Through a comprehensive characterization approach involving single crystal and powder synchrotron X-ray diffraction (XRD) in combination with the local information gained from spectroscopic techniques, we elucidated the structural features of the solids, which are all based on different inorganic secondary building units (SBUs). All the synthesized MOFs demonstrate an accessible porosity, with one of them presenting mesopores and the highest reported surface area to date for a porphyrin catecholate MOF (>2000 m 2 g -1 ). Eventually, the redox activity of these solids was investigated in a half-cell vs. Li with the aim of evaluating their potential as electrode positive materials for electrochemical energy storage. One of the solids displayed reversibility during cycling at a rather high potential (∼3.4 V vs. Li + /Li), confirming the interest of redox active phenolate ligands for applications involving electron transfer. Our findings expand the library of porphyrin-based MOFs and highlight the potential of phenolate ligands for advancing the field of MOFs for energy storage materials., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

A series of molecules that possess two quinolines, benzoquinolines, or phenanthrolines connected in a chiral fashion by a biaryl junction along with their water-soluble derivatives was developed and characterized. The influence of the structure on the basicity of the nitrogen atoms in two heterocycles was examined and the photophysical and chiroptical switching activity of the compounds upon protonation was studied both experimentally and computationally. The results demonstrated that changes in the electronic structure of the protonated vs. neutral species, promoting a bathochromic shift of dominant electronic transitions and alternation of their character from π-to-π* to charge-transfer-type, when additionally accompanied by the high structural flexibility of a system, leading to changes in conformational preferences upon proton binding, produce particularly pronounced modifications of the spectral properties in acidic medium. The latter combined with reversibility of the read-out make some of the molecules in this series very promising multifunctional pH probes.

We report the synthesis and absolute configuration (AC) of a chiral isotopologue of syn -cryptophane-B. Low chiral signatures were measured by polarimetry and electronic circular dichroism, whereas most significant chiroptical effects were observed by vibrational circular dichroism (VCD) and Raman optical activity (ROA). The comparison of experimental VCD and ROA spectra with those predicted by DFT calculations allows the determination of the AC of the two enantiomers as (-) 589 - MP - syn - 2 and (+) 589 - PM - syn - 2 .

The title Schiff base, C 20 H 14 ClNO, obtained from the reaction of 4-chloro aniline with benzil, has an approximate T shape. The dihedral angle between the phenyl rings of the benzil unit is 74.14 (15)°. The extended structure features C-H⋯O hydrogen bonds., (© Ziani et al. 2023.)

We report in this article the synthesis, the X-ray crystal structure of compound syn - 2 , and its binding properties with cesium and thallium in aqueous solution under basic conditions. Compound syn - 2 is the diastereomeric compound of anti - 1 that shows very high affinity for cesium and thallium in aqueous solution under the same conditions. Despite the close structural similarities that exist between the syn - 2 and anti - 1 compounds, they show large discrepancy in their ability to bind cesium and thallium cations in the same conditions. Indeed, the syn - 2 derivative has a lower affinity for these two cationic species and the binding constants are several orders of magnitude lower than those found for its congener. The large differences in affinity observed with these two compounds can be explained by the relative position of the six hydroxyl groups to each other., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Trifluorometylselenolation via C-H activation is barely described in literature. In particular, no such vinylic functionalization has been yet described. Herein, a palladium-catalyzed trifluoromethylselenolation of vinylic C-H bonds is described. The 5-methoxy-8-aminoquinoline has been used as auxiliary directing group to perform this reaction. The reaction gives excellent yields with α-substituted compounds whatever the substituents and a microwave activation can be used to accelerate the reaction. With β-substituted substrates lower yields, but still satisfactory, are obtained. This methodology was also successfully extended to other fluoroalkylselenyl groups., (© 2022 Wiley-VCH GmbH.)

We report an original alkane elimination approach, entailing the protonolysis of triisobutylaluminum by the acidic hydrides from Cp*IrH 4 . This strategy allows access to a series of well-defined tri- and tetranuclear iridium aluminum polyhydride clusters, depending on the stoichiometry: [Cp*IrH 3 Al( i Bu) 2 ] 2 ( 1 ), [Cp*IrH 2 Al( i Bu)] 2 ( 2 ), [(Cp*IrH 3 ) 2 Al( i Bu)] ( 3 ), and [(Cp*IrH 3 ) 3 Al] ( 4 ). Contrary to most transition-metal aluminohydride complexes, which can be considered as [AlH x +3 ] x- aluminates and LnM + moieties, the situation here is reversed: These complexes have original structures that are best described as [Cp*IrH x ] n - iridate units surrounding cationic Al(III) fragments. This is corroborated by reactivity studies, which show that the hydrides are always retained at the iridium sites and that the [Cp*IrH 3 ] - moieties are labile and can be transmetalated to yield potassium ([KIrCp*H 3 ], 8 ) or silver (([AgIrCp*H 3 ] n , 10 ) derivatives of potential synthetic interest. DFT calculations show that the bonding situation can vary in these systems, from 3-center 2-electron hydride-bridged Lewis adducts of the form Ir-H⇀Al to direct polarized metal-metal interaction from donation of d -electrons of Ir to the Al metal, and both types of interactions take place to some extent in each of these clusters.

We report the synthesis of C 3 -symmetric cryptophanes decorated with three aromatic amine groups on the same CTB cap and their interaction with xenon. The relative stereochemistry of these two stereoisomers syn and anti was assessed thanks to the determination of the X-ray structure of an intermediate compound. As previously observed with the tris-aza-cryptophanes analogs anti - 1 and syn - 2 ( J. Org. Chem . 2021 , 86 , 11, 7648-7658), both compounds anti - 5 and syn - 6 show a slow in-out exchange dynamics of xenon at 11.7 T. Our work supports the idea that the presence of nitrogen atoms grafted directly onto the cryptophane backbone has a strong impact on the in-out exchange dynamics of xenon whatever their stereochemistry. This result contrasts with the case of other cryptophanes decorated solely with methoxy substituents. Finally, we demonstrate that these new derivatives can be used to design new anti / syn cryptophanes bearing suitable ligands in order to constitute potent 129 Xe NMR-based sensors. An example is reported here with the synthesis of the tris-iodo derivatives anti - 13 and syn - 14 from compounds anti - 5 and syn - 6 .

Fast (60 kHz) magic angle spinning solid-state NMR allows very sensitive proton detection in highly paramagnetic organometallic powders. We showcase this technique with the complete assignment of 1 H and 13 C resonances in a high-spin Fe(ii) polymerisation catalyst with less than 2 mg of sample at natural abundance., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)