Merging C–H Vinylation with Switchable 6π-Electrocyclizations for Divergent Heterocycle Synthesis
Merging C–H Vinylation with Switchable 6π-Electrocyclizations for Divergent Heterocycle Synthesis
复制标题
将 C–H 乙烯基化与可切换的 6Ï-电环化相结合以实现发散杂环合成
DOI：
10.1021/jacs.0c07680
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发表时间：
2020
影响因子：
15
通讯作者：
ong Zhang
中科院分区：
文献类型：
--
作者：
Xunjin Jiang;Zhixiong Zeng;Yuhui Hua;Yifan Wu;Beibei Xu;Yang Shen;Jing Xiong;Huijuan Qiu;Tianhui Hu;Y;ong Zhang
含吡啶多杂环化合物具有独特的生物学性质和良好的电化学性质和光学性质，被广泛应用于药物、功能材料和光催化剂等领域。在这里，我们描述了一个统一的两步策略，将Rh催化的C-H乙烯化反应与两个可切换的电环化反应相结合，包括aza-6π-电环化和全碳-6π-电环化，用于快速和分散地获得二氢吡啶异喹啉和二氢苯并喹啉。通过计算表明，无论是在热条件下还是在光化学条件下，在合适的“HCl”源存在下，氮杂电环化反应的高选择性都是由于前线轨道的有利动力学和对称性所致。我们通过合成几个含吡啶的复杂多杂环化合物进一步证明了这一方案的价值，其中包括两个生物碱黄连素和白屈菜红碱。
Pyridinium-containing polyheterocycles exhibit distinctive biological properties and interesting electrochemical and optical properties and thus are widely used as drugs, functional materials, and photocatalysts. Here, we describe a unified two-step strategy by merging Rh-catalyzed C–H vinylation with two switchable electrocyclizations, including aza-6π-electrocyclization and all-carbon-6π-electrocyclization, for rapid and divergent access to dihydropyridoisoquinoliniums and dihydrobenzoquinolines. Through computation, the high selectivity of aza-electrocyclization in the presence of an appropriate “HCl” source under either thermal conditions or photochemical conditions is shown to result from the favorable kinetics and symmetries of frontier orbitals. We further demonstrated the value of this protocol by the synthesis of several complex pyridinium-containing polyheterocycles, including the two alkaloids berberine and chelerythrine.