1201896-12-9Relevant academic research and scientific papers
Halogen-bonding interaction stabilizing cluster-type diastereomeric salt crystals
Kobayashi, Yuka,Maeda, Jin,Ando, Tetsuo,Saigo, Kazuhiko
, p. 685 - 690 (2011/10/09)
O-Ethyl 4-chlorophenylphosphonothioic acid (1) was newly synthesized and applied as a chiral selector for the enantioseparation of racemic l-(4-halophenyl)ethylamines (halo = F, Cl, Br, I; 2a-d) through diastereomeric salt formation. The phosphonothioic acid 1 showed an excellent chirality-recognition ability for the fluorinated and iodinated amines 2a and 2d with the dramatic switch of the absolute configuration of the enantio-enriched isomers in the deposited salts from R for the amine 2a to S for the amine 2d. The X-ray crystallographic analyses of the four pairs of diastereomeric salts revealed that halogen-bonding interaction in the salt crystals plays a very important role for the switch.
