Herein, we report the chiral symmetry breaking of 2-methoxy-1-naphthamide atropisomers through temperature cycling without the use of any racemization reagent. The racemization rate (k 1 ) controls the deracemization process when the cooling of the slurry is slow enough to keep the system close to equilibrium. The productivity appears proportional to the racemization rate (k 1 ) multiplied by the solubility.

Temperature-cycle-induced deracemization (TCID) has been widely studied in the field of chiral separation, ranging from fundamental research to applications. In this study, the secondorder asymmetric transformation (SOAT) of 2-methoxy-1-naphthamide in an azeotropic mixture of ethyl acetate and cyclohexane is compared with TCID, in terms of process productivity. The results indicate that the volumetric productivity using SOAT was over 100times higher than that using TCID, such that a scale-up by a factor of 10 was easily implemented.

A productive deracemization process based on a quaternary phase diagram study of a naphthamide derivative is reported. New racemic compounds of an atropisomeric naphthamide derivative have been discovered, and a quaternary phase diagram has been constructed that indicated that four solids are stable in a methanol/H2O solution. Based on the results of a heterogeneous equilibria study showing the stable domain of the conglomerate, a second‐order asymmetric transformation was achieved with up to 97 % ee. Furthermore, this methodology showcases the chiral separation of a stable racemic compound forming system and does not suffer from any of the typical limitations of deracemization, although application is still limited to conglomerate‐forming systems. We anticipate that this present study will serve as a fundamental model for the design of sophisticated chiral separation processes.

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Quasi single-crystal-to-single-crystal transformation of a hydrogen-bonded organic framework (HOF) was accurately revealed and the mechanism was proposed. Interestingly, Br/π interaction allows to solve the crystal structure of intermediate phase as...

Porous frameworks composed of non‐stoichiometrically mixed multicomponent molecules attract much attention from a functional viewpoint. However, their designed preparation and precise structural characterization remain challenging. Herein, we demonstrate that cocrystallization of tetrakis(4‐carboxyphenyl)hexahydropyrene and pyrene derivatives (CP‐Hp and CP‐Py, respectively) yields non‐stoichiometric mixed frameworks through networking via hydrogen bonding. The composition ratio of CP‐Hp and CP‐Py in the framework was determined by single crystalline X‐ray crystallographic analysis, indicating that the mixed frameworks were formed over a wide range of composition ratios. Furthermore, microscopic Raman spectroscopy on the single crystal indicates that the components are not uniformly distributed such as ideal solid solution, but are done gradationally or inhomogeneously.

In reticular chemistry, many studies have attempted to design a series of isostructural frameworks with specific structures and properties by manipulating the constituent molecules. Frameworks constructed through non-covalent interactions, such...

Preparation and characterizationfp orous frameworks composed of non-stoichiometrically mixed multicomponent molecules has been ac hallenge.I nt heir Communication (e202215836), Ichiro Hisaki et al. demonstrate that cocrystallization of hexahydropyrene and pyrene derivatives yields such frameworks through ahydrogen-bonded network. Thecomposition ratio in the framework was determined crystallographically.