Arumugaperumal Reguram, Srinivasadesikan Venkatesan, Ramakrishnam Raju Mandapati V, Lin Ming-Chang, Shukla Tarun, Singh Ravinder, Lin Hong-Cheu
Department of Materials Science and Engineering, National Chiao Tung University , Hsinchu 300, Taiwan.
Center for Interdisciplinary Molecular Science, Department of Applied Chemistry, National Chiao Tung University , Hsinchu 300, Taiwan.
ACS Appl Mater Interfaces. 2015 Dec 9;7(48):26491-503. doi: 10.1021/acsami.5b07574. Epub 2015 Nov 20.
A novel multifunctional mechanically interlocked switchable [2]rotaxane R4 containing two molecular stations and rotaxane arms terminated with boron-dipyrromethene (BODIPY) fluorophores and its derivatives were synthesized for the first time by CuAAC click reaction. The shuttling motion of macrocycle between the dibenzylammonium and triazolium recognition sites and the distance dependent photoinduced electron transfer process of R4 is demonstrated by utilizing external chemical stimuli (acid/base). Interestingly, the reversible self-assembly process of R4 was recognized by the acid-base molecular switch strategy. Notably, two symmetrical triazolium groups acted as molecular stations, H2PO4(-) receptors, and H-bonded donors. Both [2]rotaxane R4 and thread R2 demonstrated excellent optical responses and high selectivity toward H2PO4(-) ion. The specific motion and guest-host interactions of mechanically interlocked machines (MIMs) were also further explored by quantum mechanical calculations. The thread R2 also demonstrated to enable the detection of H2PO4(-) in RAW 264.7 cells successfully.
通过铜催化的叠氮-炔环加成（CuAAC）点击反应首次合成了一种新型多功能机械互锁的可切换[2]轮烷R4，其包含两个分子站点以及以硼二吡咯亚甲基（BODIPY）荧光团及其衍生物为末端的轮烷臂。利用外部化学刺激（酸/碱）证明了大环在二苄基铵和三唑鎓识别位点之间的穿梭运动以及R4的距离依赖性光诱导电子转移过程。有趣的是，R4的可逆自组装过程通过酸碱分子开关策略得以识别。值得注意的是，两个对称的三唑鎓基团充当分子站点、H2PO4(-)受体和氢键供体。[2]轮烷R4和线轴R2对H2PO4(-)离子均表现出优异的光学响应和高选择性。还通过量子力学计算进一步探索了机械互锁机器（MIMs）的特定运动和客体-主体相互作用。线轴R2还成功证明能够检测RAW 264.7细胞中的H2PO4(-)。
