An isolable phenylborylene species supported by two oxazol-2-ylidene ligands was synthesized and structurally characterized. Computational studies revealed the presence of lone-pair electrons on the boron atom in this molecule; therefore, there are eight electrons around the three-coordinate boron center. The nucleophilic property was confirmed by the reactions with trifluoromethanesulfonic acid and [(thf)Cr(CO) 5 ], which gave the corresponding conjugate acid and a chromium-borylene complex, respectively.

The ability to rationally design and predictably construct crystalline solids has been the hallmark of crystal engineering research. To date,n umerous examples of multicomponent crystals comprising organic molecules have been reported. However,t he crystal engineering of cocrystals comprising both organic and inorganic chemical units is still poorly understood and mostly unexplored. Here,w er eport anew diverse set of higher-order cocrystals (HOCs) based on the structurally versatile-yet largely unexplored-phosph(V/ V)azane heterosynthon building block. The novel ternary and quaternary cocrystals reported are held together by synergistic and orthogonal intermolecular interactions.N otably,t he HOCs can be readily obtained either via sequential or onepot mechanochemical methods.C omputational modelling methods reveal that the HOCs are thermodynamically driven to form and that their mechanical properties strongly depend on the composition and intermolecular forces in the crystal, offering untapped potential for optimizing material properties.

Success in obtaining high twistarenes with precise structures is very important because such an approach could provide a lot of useful information in fundamentally understanding the relationship between structures and physical properties/optoelectronic applications.

We have synthesized ac ompletely new family of acyclic trimeric cyclodiphosphazane compounds comprising NH, N i Pr,N t Bu and NPh bridging groups.Inaddition, the first NH-bridged acyclic dimeric cyclophosphazane has been produced. The trimeric species display highly tuneable characteristics so that the distance between the terminal N(H)R moieties can be readily modulated by the steric bulk present in the bridging groups (ranging from % 6t o% 10). Moreover, these species exhibit pronounced topological changes when aw eak non-bonding NH•••p aryl interaction is introduced. Finally,t he NH-bridged chloride binding affinities have been calculated and benchmarked along with the existing experimental data available for monomeric cyclodiphosphazanes. Our results underscore these species as promising hydrogen bond donors for supramolecular host-guest applications.