Asymmetric Diels-Alder reaction was achieved under achiral conditions. Reaction of prochiral 2-methylfuran and N-phenylmaleimide in heptane or hexane solution at 80 °C efficiently gave a conglomerate crystal of exo-type Diels-Alder adduct selectively, and continuous suspension of the reaction mixture with glass beads promoted attrition-enhanced deracemization, leading to an optically active exo-adduct in 90% ee.

Efficient generation and amplification of chirality from prochiral substrates in the Diels–Alder reaction (DA reaction) followed by dynamic crystallization were achieved without using an external chiral source. Since the DA reaction of 2-methylfuran and various maleimides proceeds reversibly, an exo-adduct was obtained as the main product as the reaction proceeded. From single crystal X-ray structure analysis, it was found that five of ten exo-adducts gave conglomerates. When 2-methylfuran and various maleimides with a catalytic amount of TFA were reacted in a sealed tube, the exo-DA adducts were precipitated from the solution, while the reaction mixtures were continuously ground and stirred using glass beads. Deracemization occurred and chiral amplification was observed for four of the substrates. Each final enantiomeric purity was influenced by the crystal structure, and when enantiomers were included in the disorder, they reached an enantiomeric purity reflecting the ratio of the disorder. The final ee value of the 3,5-dimethylphenyl derivative after chiral amplification was 98% ee.

The study of chirogenesis of organic molecules is important to elucidate the origin of the homochirality of biomolecules on Earth. Here, we have accomplished chiral symmetry breaking from a racemate using optical vortices with orbital angular momentum and a helical wavefront. We propose a new methodology of asymmetric transformation by the combination of enantioselective crystal nucleation by irradiation with optical vortices and crystallization-induced dynamic optical resolution of conglomerate crystals. Chiral green vortices generated using a spiral phase plate (SPP) with a 532 nm CW-laser were used to irradiate a supersaturated solution of a racemic isoindolinone, leading to crystal nucleation. The handedness of the crystals were controlled by the winding direction of the chiral optical vortices. The molecular chirality of the isoindolinone was then amplified by dynamic crystallization.

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Practical synthesis of bay-monofunctionalized perylene dyes has been developed based on controllable NBS bromination of tetrabenzyl perylene-3,4,9,10-tetracarboxylate. The ability to perform the convenient and high-yielding synthesis highlights the potential utility of our multifunctional approach to access a diverse range of new perylene systems.