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The solid‐state synthesis and fast crystallization under kinetic control of poly‐[n]‐catenanes self‐assembled of mechanically interlocked metal organic cages (MOCs) is virtually unexplored. This is in part, due to the lack of suitable crystals for single crystal X‐ray diffraction (SC‐XRD) analysis which limits their progress as advanced functional materials. Here we report the unprecedented inclusion of paracetamol in the cavities of amorphous materials constituted of M12L8, interlocked MOCs synthesized by mechanochemistry under kinetic control. Full structure determination of a low‐crystallinity and low‐resolution powders of the M12L8 poly‐[n]‐catenane including paracetamol has been carried out combining XRD data and Density Functional Theory (DFT) calculations using a multi‐step approach. Each M12L8 cage contains six paracetamol guests which is confirmed by thermal analysis and NMR spectroscopy. The paracetamol loading has been also carried out by the instant synthesis method using a saturated paracetamol solution in which TPB and ZnI2 self‐assemble immediately (i. e., 1–5 seconds) encapsulating ~7 paracetamol molecules in the M12L8 nanocages under kinetic control also giving a good selectivity. Benzaldehyde has been included in the M12L8 cages using amorphous M12L8 polycatenanes showing that the icosahedral cages can serve as potential nanoreactors for instance to study Henry reactions in the solid‐state. [ABSTRACT FROM AUTHOR]

Here, we show that in a supramolecular system with more than 20 building blocks forming large icosahedral M12L8 metal–organic cages (MOCs), using the instant synthesis method, it is possible to kinetically trap and control the formation of interlocking M12L8 nanocages, giving rare M12L8 TPB-ZnI2 poly-[n]-catenane. The catenanes are obtained in a one-pot reaction, selectively as amorphous (a1) or crystalline states, as demonstrated by powder X-ray diffraction (powder XRD), thermogravimetric (TG) analysis and 1H NMR. The 300 K M12L8 poly-[n]-catenane single crystal X-ray diffraction (SC-XRD) structure including nitrobenzene (1) indicates strong guest binding with the large M12L8 cage (i.e., internal volume ca. 2600 Å3), allowing its structural resolution. Conversely, slow self-assembly (5 days) leads to a mixture of the M12L8 poly-[n]-catenane and a new TPB-ZnI2 (2) coordination polymer (i.e., thermodynamic product), as revealed by SC-XRD. The neat grinding solid-state synthesis also yields amorphous M12L8 poly-[n]-catenane (a1′), but not coordination polymers, selectively in 15 min. The dynamic behavior of the M12L8 poly-[n]-catenanes demonstrated by the amorphous-to-crystalline transformation upon the uptake of ortho-, meta- and para-xylenes shows the potential of M12L8 poly-[n]-catenanes as functional materials in molecular separation. Finally, combining SC-XRD of 1 and DFT calculations specific for the solid-state, the role of the guests in the stability of the 1D chains of M12L8 nanocages is reported. Energy interactions such as interaction energies (E), lattice energies (E*), host–guest energies (Ehost-guest) and guest-guest energies (Eguest-guest) were analysed considering the X-ray structure with and without the nitrobenzene guest. Not only the synthetic control achieved in the synthesis of the M12L8 MOCs but also their dynamic behavior either in the crystalline or amorphous phase are sufficient to raise scientific interest in areas ranging from fundamental to applied sides of chemistry and material sciences. [ABSTRACT FROM AUTHOR]

De novo metalloprotein design is a remarkable approach to shape protein scaffolds toward specific functions. Here, we report the design and characterization of Due Rame 1 (DR1), a de novo designed protein housing a di‐copper site and mimicking the Type 3 (T3) copper‐containing polyphenol oxidases (PPOs). To achieve this goal, we hierarchically designed the first and the second di‐metal coordination spheres to engineer the di‐copper site into a simple four‐helix bundle scaffold. Spectroscopic, thermodynamic, and functional characterization revealed that DR1 recapitulates the T3 copper site, supporting different copper redox states, and being active in the O2‐dependent oxidation of catechols to o‐quinones. Careful design of the residues lining the substrate access site endows DR1 with substrate recognition, as revealed by Hammet analysis and computational studies on substituted catechols. This study represents a premier example in the construction of a functional T3 copper site into a designed four‐helix bundle protein. [ABSTRACT FROM AUTHOR]

Ab initio calculations of the conformational effects produced by substitution of 2,2'-bithiophene (T2) with one or two fluorine, methoxy, methyl, or chlorine groups in one or both 3 positions, are presented. The fluorine and methoxy substituents enhance the coplanarity of the rings, whereas methyl and chlorine behave similarly by producing greater distortion.

A nonorthogonal configuration interaction scheme (MO-VB) is discussed by means of an iterative optimization approach in order to evaluate intermolecular forces, to determine optimal virtual orbitals, and to contract the virtual space spanned by all singly and doubly excited localized configurations. The method is applied on three weakly interacting complexes He2, He-Ch4 and He-H20 to test the theoretical framework of approach, which defines a variational VB (valance bond) wave function, consisting of singly and doubly excitations from the self-consistent field for molecular interactions (SCF-MI) determinants.