Memory of Chirality Generated by Spontaneous Crystallization and Asymmetric Synthesis Using the Frozen Chirality

Asymmetric synthesis using frozen chirality generated by spontaneous crystallization was performed. Achiral asymmetrically substituted imide with a tetrahydronaphthyl group on the nitrogen atom crystallized in a chiral fashion, with space group P212121. The molecular chirality generated by spontaneous crystallization was retained in cold THF. The half-life determined on the basis of decreasing optical activity followed by CD spectrometer was 7.8, 33.1, and 150.0 min at −20, −30, −40 °C, respectively. The energy barrier (ΔG⧧) of racemization was calculated with the temperature dependence of the kinetic constant to be 18.24−18.36 kcal mol-1 at 233−253 K. The memorized frozen chirality was transferred to permanent optically active alcohols by nucleophilic addition with n-buthyllithium.