Stereoselective Solid-State Synthesis of Substituted Cyclobutanes Assisted by Pseudorotaxane-like MOFs
Stereoselective Solid-State Synthesis of Substituted Cyclobutanes Assisted by Pseudorotaxane-like MOFs
复制标题
拟轮烷类MOF辅助立体选择性固态合成取代环丁烷
DOI：
10.1002/anie.201806076
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发表时间：
2018-09-24
影响因子：
16.6
通讯作者：
Lang, Jian-Ping
中科院分区：
文献类型：
--
作者：
Hu, Fei-Long;Mi, Yan;Lang, Jian-Ping
以拟紫杉烷类锌基金属有机骨架MOF为模板，进行了反式-4-苯基吡啶(4-SPY)衍生物的区域选择性光二聚反应。RCTT-HT(Head-to-Tail)二聚体的形成是通过将配位的4-spy衍生配体对限制在六角形窗口内，然后用紫外光照射它们来实现的。还有可能实现光二聚反应，其中在这种MOF材料中包括两个不同的取代的4-spy配体。在以CH3O-SPY为基础的MOF中，利用醚键的形成来保护HO-SPY中敏感的-OH基团，然后在CH3O-SPY中形成环丁烷衍生物后，CH3O-SPY的甲基被去除。在4-SPY的苯基的2-或3-位引入取代基不会显著影响二聚反应的速率，除非是强吸电子的硝基，其速率显著降低。这些结果与有机溶剂中非模板光二聚得到的光产物和低产率的混合物形成了鲜明的对比。
Regioselective photodimerization of trans-4-styrylpyridine (4-spy) derivatives is performed using pseudorotaxane-like Zn-based metal organic frameworks MOFs as templates. The formation of rctt-HT (head-to-tail) dimers is achieved by confining pairs of coordinated 4-spy derivative ligands within hexagonal windows and then irradiating them with UV light. It is also possible to achieve a photodimerization reaction where two different substituted 4-spy ligands are included in such a MOF material. The ether bond formation is employed to protect the sensitive -OH group of HO-spy and the methyl group of CH3O-spy is subsequently removed after the formation of cyclobutane derivative in the CH3O-spy-based MOF. Introducing substituents at the 2- or 3-position of the phenyl group of 4-spy does not significantly affect the rate of the dimerization process except in the case of the strongly electron-withdrawing nitro group where the rate is significantly decreased. These results are in striking contrast to the mixtures of photoproducts and low yields obtained by untemplated photodimerization in organic solvents.