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Isostructural crystals are crucial for the development of high-performance functional materials and precise control over physicochemical properties, whereas the design of isostructural crystals is extremely challenging. In this work single-component isostructural crystals were obtained with the substitution of side-chain groups. High-quality single crystals of isostructural crystals methyl 2-amino-5-methylbenzoate (MAMB) and methyl 2-amino-5-methoxybenzoate (MAMOB) were harvested through sublimation crystallization. Their crystal structures were determined by single-crystal X-ray diffraction (SCXRD). Similar intermolecular interactions and packing modes suggested that MAMB and MAMOB are 3D isostructural, and the quantitative similarity parameters were calculated via the XPac program. Furthermore, these two obtained isostructural crystals exhibited similar blue light emission behaviors and solvation effects. [ABSTRACT FROM AUTHOR]

The preparation of a cocrystal is one of the effective strategies to tune the luminescence properties of organic crystals. In this work, four charge transfer cocrystals were constructed with isomeric substances of amino substituted dimethyl phthalates as the donors and 1,2,4,5-tetracyanobenzene as the acceptor. The emission range of the individual electron donors is from 400 nm to 505 nm, while all cocrystals have their emission redshift exceeding 100 nm. The tunable emission range of the charge transfer cocrystals is from 573 nm to 640 nm. All the obtained four cocrystals contain π–π stacking structures with the presence of π–π and C–H⋯π interactions. Fourier transform infrared spectroscopy and UV-vis spectroscopy demonstrated the presence of charge transfer interactions in the cocrystals. The tuning of the luminescence properties of the cocrystals was explained by the analysis of the crystal packing structure and the intermolecular interaction, and the distribution of frontier orbitals was obtained by DFT calculation. We believe our work is helpful to understand the relationship between the crystal structure and luminescence properties in the charge transfer cocrystals and provide guidance for the modulation of the luminescence properties. [ABSTRACT FROM AUTHOR]

A novel one‐pot deracemization method using a bifunctional chiral agent (BCA) is proposed for the first time to convert a racemate to the desired enantiomer. Specifically, chiral α, (α‐diphenyl‐2‐pyrrolidinemethanol) formed enantiospecific cocrystals with racemic dihydromyricetin, and used its own alkaline catalysis to catalyze the racemization between the (2R,3R)‐enantiomer and (2S,3S)‐enantiomer in solution, achieving a one‐pot spontaneous deracemization. This strategy was also successfully extended to the deracemization of three other racemic compound drugs: (R,S)‐carprofen, (R,S)‐indoprofen, and (R,S)‐indobufen. The one‐pot deracemization method based on the BCA strategy provides a feasible approach to address the incompatibility between cocrystallization and racemization reactions that are commonly encountered in the cocrystallization‐induced deracemization process and opens a new window to develop essential enantiomerically pure pharmaceutical products with atom economy. [ABSTRACT FROM AUTHOR]