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Herein we report the highly selective radical chlorination of 2,2-difluorobicyclo[1.1.1]­pentane-1,3-dicarboxylic acid. Together with radical hydrodechlorination by TMS3SiH, four new bicyclo[1.1.1]­pentane cages carrying two fluorine and one to three chlorine atoms in bridge positions have been obtained. The exact positions of all halogen atoms have been confirmed by X-ray diffraction. The acidity constants (pK a) for all new derivatives have been determined by capillary electrophoresis, and these experimental values show excellent agreement with pK as predicted by DFT methods. Extensive DFT calculations have been used to rationalize the selective formation of four out of nine possible F2Cl1–4 isomers of bridge-halogenated bicyclo[1.1.1]­pentanes and to obtain relative strain energies for all possible isomers.

Fluorinated Metal-Organic Frameworks (MOFs), comprising a wheel-shaped ligand with geminal rotating fluorine atoms, produced benchmark mobility of correlated dipolar rotors at 2 K, with practically null activation energy (E a = 17 cal mol À 1 ). 1 H T 1 NMR revealed multiple relaxation phenomena due to the exchange among correlated dipole-rotor configurations. Synchrotron radiation X-ray diffraction at 4 K, Density Functional Theory, Molecular Dynamics and phonon calculations showed the fluid landscape and pointed out a cascade mechanism converting dipole configurations into each other. Gas accessibility, shown by hyperpolarized-Xe NMR, allowed for chemical stimuli intervention: CO 2 triggered dipole reorientation, reducing their collective dynamics and stimulating a dipole configuration change in the crystal. Dynamic materials under limited thermal noise and high responsiveness enable the fabrication of molecular machines with low energy dissipation and controllable dynamics.

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Eight new geranylated and farnesylated pyranoflavanones (1–8) and two new farnesylated pyranochalcones (9 and 10) were isolated from the methanolic extract of the fruits of Amomum tsao-ko. Their structures were elucidated by extensive analysis of the 1D and 2D NMR spectra and from the HRESIMS, combined with experimental ECD data. All compounds were evaluated for their inhibitory effects on the nitric oxide production against lipopolysaccharide-induced RAW 264.7 macrophages and exhibited IC50 values ranging from 10.6 to 41.5 μM.