Direct assignment of the absolute configuration of molecules from crystal morphology.
A method for direct assignment of the absolute configuration of molecules and the absolute structures of polar crystals, independent to that of Bijvoet, is described. The method correlates between the two-dimensional packing arrangement of specific faces, that delineate crystals during their growth and dissolution, with molecules present in the environment. The structural information stored in these faces is transferred to "tailor-made" molecules added to the solvent by controlled morphological changes induced to the growing crystals and by the creation of etch pits at specific crystal faces during their dissolution. In addition, the "tailor-made" molecules are occluded enantioselectively as guests within specific sectors of the host crystals. The method is illustrated for a variety of molecules and crystals including the assignment of the absolute configuration of several alpha-amino acids as "tailor-made" additives in centrosymmetric crystals of glycine and serine, for the absolute structure of polar crystals of sugars and alpha-amino acids and consequently the absolute configuration of molecules packed in such crystals.
Weissbuch
Isabelle
I
Department of Materials and Interfaces, The Weizmann Institute of Science, Rehovot, Israel.
Leiserowitz
Leslie
L
Lahav
Meir
M