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Two MOFs were reported based on Zn(II) with 1,2-bis (4-pyridyl)hydrazine (L1); a two-dimensional interpenetrating MOF I of formula [[[Zn.sub.2][(L1).sub.2][(L2).sub.2]] .sub.∞] was formed with terephthalic acid (L2) as an additional linker. A three-dimensional MOF II of formula [[[Zn.sub.2][(L1).sub.2][(L3).sub.2]].sub.∞] was formed with the use of a larger spacer 2,6- naphthalenedicarboxylic acid (L3). MOF II consists of large porosity with a total volume of 3746 [Å.sup.3] that occupies 34.1% of the unit cell. Key words: metal organic framework, coordination polymer, 1,2-bis(4-pyridyl)hydrazine, interpenetrating polymer, microporous, hydrogen bond. On rapporte les proprietes de deux charpentes organometalliques (COM) a base de Zn(II) et de 1,2-bis(4- pyridyl)hydrazine (L1); un COM bidimensionnelle imbriquee (I) de formule [[[Zn.sub.2][(L1).sub.2][(L2).sub.2]].sub.∞] forme a l'aide d'acide terephtalique (L2) utilise comme coupleur additionnel. Il se forme aussi une COM tridimensionnelle (II) de formule [[[Zn.sub.2][(L1).sub.2](L3).sub.2].sub.∞] lorsqu'on utilise l'acide naphtalene-2,6-dicarboxylique (L3) comme coupleur plus long. La charpente organometallique II possede une grande porosite, avec un volume total de 3746 [Å.sup.3] qui occupe 34,1 % de la maille elementaire. Mots-cles : charpente organometallique, polymere de coordination, 1,2-bis(4-pyridyl)hydrazine, polymere imbrique, microporeux, liaison hydrogene. [Traduit par la Redaction], Introduction Metal-organic frameworks (MOFs) have attracted much attention in the past decade because of their well-organized three-dimensional forms with permanent porosity, as well as their potential applications in adsorption, separation, [...]

Chirality is ubiquitous within biological systems where many of the roles and functions are still undetermined. Given this, there is a clear need to design and develop sensitive chiral optical probes that can function within a biological setting. Here we report the design and synthesis of magnetically responsive Circularly Polarized Luminescence (CPL) complexes displaying exceptional photophysical properties (quantum yield up to 31 % and |glum| up to 0.240) by introducing chiral substituents onto the macrocyclic scaffolds. Magnetic CPL responses are observed in these chiral EuIII complexes, promoting an exciting development to the field of magneto‐optics. The |glum| of the 5D0 → 7F1 transition increases by 20 % from 0.222 (0 T) to 0.266 (1.4 T) displaying a linear relationship between the Δglum and the magnetic field strength. These EuIII complexes with magnetic CPL responses, provides potential development to be used in CPL imaging applications due to improved sensitivity and resolution. [ABSTRACT FROM AUTHOR]

Triboluminescence (TL) is a form of light emission induced upon mechanical forces on the material. However, our understanding of this phenomenon is still unclear and more examples are therefore needed in order to elucidate its mechanism. In this work, two types of TL complexes, [Eu(pp-dbm-Cl2)3phen] and [Eu(mm-dbm-Cl2)3phen], which also displays aggregation-induced emission (AIE) were synthesized and investigated for its photo-physical and crystal structural properties. These complexes were crystallized in a centro-symmetric space group P21/n, and remarkably, displayed TL upon grinding that may be due to the presence of extensive π···π, C-H···π and C-H···Cl-C interactions in the close molecular packing of its structure. This rare example deviates from the widely accepted mechanism of TL, hence widening the scope of our understanding in the area. [ABSTRACT FROM AUTHOR]

The synthesis of a new CF3-containing stereogenic atropisomeric pair of ortho-disubstituted biphenyl scaffold is presented. The atropisomers are surprisingly conformationally stable for isolation. X-ray structures show that their stability comes from an intramolecular hydrogen bond formation from their two hydroxyl groups and renders the spatial arrangement of their peripheral CF3 and CH3 groups very different. The synthesized stereogenic scaffold proved to be effective in catalyzing the asymmetric N-nitroso aldol reaction of enamine and nitrosobenzene. Compared to similar scaffolds without CF3 groups, one of our atropisomer exhibits an increase in enantioselectivity in this reaction. [ABSTRACT FROM AUTHOR]

A versatile π-extension reaction was developed based on the three-component cross-coupling of aryl halides, 2-haloarylcarboxylic acids, and norbornadiene. The transformation is driven by the direction and subsequent decarboxylation of the carboxyl group, while norbornadiene serves as an ortho-C-H activator and ethylene synthon via a retro-Diels-Alder reaction. Comprehensive DFT calculations were performed to account for the catalytic intermediates., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The hydrolysis of [ClP(mu-NtBu)]2 with H2O-Et3N in thf, followed by in situ lithiation with nBuLi gives the Li13 cage [[[O-P(mu-NtBu)]2Li2]3(LiCl)6Li(Cl/OnBu)0.5(thf)7], containing a [O-P(mu-NtBu)]2(2-) dianion that is isoelectronic with ligands of the type [(RN)P(mu-NR)]2(2-).