Frozen: The spontaneous crystallization of an achiral compound in a chiral conformation is used as the unique source of chirality in an absolute asymmetric synthesis of tertiary amino acids. The dynamic axial chirality of tertiary aromatic amides is frozen in a crystal (see picture) and is responsible for the stereoselectivity of the deprotonation/alkylation (see scheme). α-Amino acid derivatives are synthesized in up to 96 % ee.
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