Stereoselective Copper-Catalyzed Olefination of Imines.
Stereoselective Copper-Catalyzed Olefination of Imines.
复制标题
亚胺的立体选择性铜催化烯化。
DOI：
10.1002/anie.202316521
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发表时间：
2024
期刊：
影响因子：
--
通讯作者：
Lalic,Gojko
中科院分区：
文献类型：
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作者：
Baumann,JamesE;Chung,CrystalP;Lalic,Gojko
烯烃是一类重要的有机分子，存在于合成中间体和生物活性化合物中。它们通常通过使用叶立德或其等同物的羰基和亚胺的化学计量Wittig型烯化来合成。尽管维蒂希型烯烃化反应的重要性，其催化变体仍然不发达。我们探索了使用过渡金属催化剂从容易获得的起始原料形成叶立德等价物。我们的研究导致了一种新的铜催化的烯化亚胺与烯基硼酸酯作为偶联伙伴。我们确定了一个杂环络合物，通过氢化铜的烯基硼酸酯，作为关键的催化中间体，作为叶立德等价物。在反应中观察到的高E-选择性是由于该中间体与亚胺的立体选择性加成，然后是立体特异性反消除。
Alkenes are an important class of organic molecules found among synthetic intermediates and bioactive compounds. They are commonly synthesized through stoichiometric Wittig‐type olefination of carbonyls and imines, using ylides or their equivalents. Despite the importance of Wittig‐type olefination reactions, their catalytic variants remain underdeveloped. We explored the use of transition metal catalysis to form ylide equivalents from readily available starting materials. Our investigation led to a new copper‐catalyzed olefination of imines with alkenyl boronate esters as coupling partners. We identified a heterobimetallic complex, obtained by hydrocupration of the alkenyl boronate esters, as the key catalytic intermediate that serves as an ylide equivalent. The highE‐selectivity observed in the reaction is due to the stereoselective addition of this intermediate to an imine, followed by stereospecific anti‐elimination.