Department of Materials Science, University of Milano Bicocca, Via R. Cozzi 55, Milano (Italy).
Angew Chem Int Ed Engl. 2015 Apr 13;54(16):4773-7. doi: 10.1002/anie.201412412. Epub 2015 Feb 16.
New mesoporous covalent frameworks, based on hybrid fluorinated organosilicas, were prepared to realize a periodic architecture of fast molecular rotors containing dynamic dipoles in their structure. The mobile elements, designed on the basis of fluorinated p-divinylbenzene moieties, were integrated into the robust covalent structure through siloxane bonds, and showed not only the rapid dynamics of the aromatic rings (ca. 10(8) Hz at 325 K), as detected by solid-state NMR spectroscopy, but also a dielectric response typical of a fast dipole reorientation under the stimuli of an applied electric field. Furthermore, the mesochannels are open and accessible to diffusing in gas molecules, and rotor mobility could be individually regulated by I2 vapors. The iodine enters the channels of the periodic structure and reacts with the pivotal double bonds of the divinyl-fluoro-phenylene rotors, affecting their motion and the dielectric properties.
新型介孔共价框架基于混合氟化有机硅制备而成，旨在实现包含结构中动态偶极子的快速分子转子的周期性结构。基于氟化对二乙烯基苯部分设计的可移动元素通过硅氧烷键整合到坚固的共价结构中，不仅显示出芳环的快速动力学（在 325 K 下约为 10(8) Hz），如通过固态 NMR 光谱检测到的那样，而且在施加电场刺激下还表现出快速偶极子重取向的介电响应。此外，介孔通道是开放的，可让气体分子扩散，并且转子的迁移率可以通过 I2 蒸气单独调节。碘进入周期性结构的通道并与二乙烯基-氟-亚苯基转子的关键双键反应，从而影响它们的运动和介电性能。
