Enantiopure cyclic O‐substituted phenylphosphonothioic acid: Synthesis and chirality‐recognition ability |
| |
Authors: | Nigel Ribeiro Yuka Kobayashi Jin Maeda Kazuhiko Saigo |
| |
Institution: | Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, Hongo, Bunkyo‐ku, Tokyo, 113‐8656 Japan |
| |
Abstract: | As a new acidic selector (resolving agent), we synthesized an enantiopure O‐alkyl phenylphosphonothioic acid with a seven‐membered ring ((R)‐ 5 ), which was designed on the basis of the results for the enantioseparation of 1‐arylethylamine derivatives with acyclic O‐ethyl phenylphosphonothioic acid ( I ). The phosphonothioic acid (R)‐ 5 showed unique chirality‐recognition ability in the enantioseparation of 1‐naphthylethylamine derivatives, aliphatic secondary amines, and amino alcohols; the ability was complementary to that of I . The X‐ray crystallographic analyses of the less‐ and more‐soluble diastereomeric salts showed that hydrogen‐bonding networks in the salt crystals are 21‐column‐type with a single exception which is cluster‐type. In the cases of the 21‐column‐type crystals, stability of the crystals is firstly governed by hydrogen bonds to form a 21‐column and secondly determined by intra‐columnar T‐shaped CH/π interaction(s), intra‐columnar hydrogen bond(s), inter‐columnar van der Waals interaction and/or inter‐columnar T‐shaped CH/π interaction(s). In contrast, the cluster‐type salt crystal is stabilized by the assistance of inter‐cluster T‐shaped CH/π and van der Waals interactions. To realize still more numbers of intra‐ and inter‐columnar and ‐cluster T‐shaped CH/π interactions, the seven‐membered ring of (R)‐ 5 plays a considerable role. Chirality 23:438–448, 2011. © 2009 Wiley‐Liss, Inc. |
| |
Keywords: | chirality‐recognition diastereomeric salt hydrogen‐bonding network hydrogen bond T‐shaped CH/π interaction van der Waals interaction globular cluster infinite 21‐column X‐ray crystallographic analysis |
|
|