Structure and absolute configuration of liquid molecules based on adamantane derivative cocrystallization

Abstract

Liquid molecules are difficult to crystallize, and their structures and absolute configurations cannot be directly determined by X-ray crystallography. We herein report the rapid cocrystallization of tetraaryladamantanes with liquid molecules. The structure of the liquid small molecules can be obtained by determining the crystal structure of the cocrystallized compound. The absolute configuration of chiral molecules can also be assigned, which cannot be accomplished by other methods such as nuclear magnetic resonance. In this paper, liquid compounds such as phenylethanol and phenylpropanol derivatives were selected. 1,3,5,7-Tetrakis(2,4-diethoxyphenyl)adamantane (TEO) powder was heated and dissolved in liquid molecules and allowed to stand overnight to undergo cocrystallization. The results show that the single-crystal structures and the absolute configurations of 16 liquid molecules were determined by cocrystallization, and the homochiral natures of chiral compounds were confirmed by solid circular dichroism spectral measurements.