Dynamic Molecular Propeller: Supramolecular Chirality Sensing by Enhanced Chiroptical Response through the Transmission of Point Chirality to Mobile Helicity
作者:Ryo Katoono、Hidetoshi Kawai、Kenshu Fujiwara、Takanori Suzuki
DOI:10.1021/ja906810b
日期:2009.11.25
p-xylylenediammonium derivatives (R,R)/(S,S)-3 (chirality generation). Through transmission of the point chiralities attached on the nitrogens in the chiral guests to the mobile helicity in 1a-H, the propeller-shaped host in the complex is biased to prefer a particular handedness (chirality biasing). While chiral guests with simple point chiralities such as (R,R)/(S,S)-3 exhibit only very weak CD activity
连接到四个芳基叶片的二级对苯二甲酰胺主体 1a-H 由四溴化物 2a 通过 Suzuki-Miyaura 偶联制备,并且在与双位客体(如 p-苯二甲铵衍生物 (R,R)/(S,S)-3(手性生成)。通过将附着在手性客体中的氮上的点手性传递给 1a-H 中的移动螺旋,复合物中的螺旋桨状主体偏向于偏向于特定的旋向性(手性偏向性)。虽然具有简单点手性的手性客体如 (R,R)/(S,S)-3 仅表现出非常弱的 CD 活性,但与动态螺旋桨宿主 1a-H 的络合会导致更强的手性信号(手性增强)。手性生成-手性偏置协议已成功应用于神经递质 (-)-苯肾上腺素 4,充当手性双位客体。当手性助剂如 (R,R)-1b-H 中那样连接到宿主时,与 (S,S)-3 的复合会导致 CD 增强,但不会与 (R,R)-3 复合,这是由于手性识别。