Crystal structures and chiral recognition of the diastereomeric salts prepared from 2-methoxy-2-(1-naphthyl)propanoic acid
作者:Akio Ichikawa、Hiroshi Ono、Takuya Echigo、Yuji Mikata
DOI:10.1039/c1ce05155e
日期:——
to report the structures of crystalline diastereomeric salts 8 and 9 prepared from (R)-2-methoxy-2-(1-naphthyl)propanoic acid [(R)-MαNP acid, (R)-1] and (S)-1 with (R)-1-phenylethylamine [(R)-PEA, (R)-7], respectively. These crystal structures helped elucidate a novel chiral recognition mechanism characteristic of MαNP salts. The less-soluble diastereomeric salt 8 prepared from (R)-1 and (R)-7 formed
本文是首次报道结晶非对映盐的结构8和9由(- [R)-2-甲氧基-2-(1-萘基)丙酸[([R)-MαNP酸,(- [R ) - 1 ]和(S)-1与(R)-1-苯基乙胺[(R)-PEA,(R)-7 ]。这些晶体结构有助于阐明MαNP盐的新型手性识别机制。由(R)-1和(R)-7制备的难溶非对映异构体盐8通过甲氧基辅助的盐桥和芳香族CH⋯π相互作用形成铵-羧酸根离子对。由(S)-1和(R)-7制备的更易溶的非对映异构体盐9通过甲氧基辅助的盐桥形成离子对,其中1-萘基和苯基不重叠。相反,盐9借助于盐桥,CH 3 O氢键和π1π相互作用形成了紧密的离子对。这些晶体结构表明,从包含羧基和甲氧基的MαNP平面开始的分子长度对于非对映体盐的结晶至关重要。研究了两种盐在弱相互作用(即盐桥,NH 3 O和CH 3 O氢键以及芳族CH 3π,CH 3π和π3π相互作用)中的晶体堆积。最后,非对映异构酰胺1