Intermolecular [3+2] cycloaddition of cyclopropylamines with olefins by visible-light photocatalysis.
Intermolecular [3+2] cycloaddition of cyclopropylamines with olefins by visible-light photocatalysis.
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DOI：
10.1002/anie.201106162
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发表时间：
2012-01-02
影响因子：
16.6
通讯作者：
Zheng, Nan
中科院分区：
文献类型：
--
作者：
Maity, Soumitra;Zhu, Mingzhao;Shinabery, Ryan Spencer;Zheng, Nan
太阳能是清洁、丰富的，更重要的是，它是可再生的。因此，随着世界转向科学家来应对环境可持续性的挑战，任何有效地收集太阳能并将其转化为化学能的反应都比以往任何时候都更加重要。可见光(390-750纳米)占整个太阳光谱的43%。然而，许多有机分子不能有效地吸收可见光，从而限制了可见光在有机合成中的使用。这个问题的一个可能的解决方案包括使用可见光光氧化还原催化剂，如Ru[1]或Ir[2]多吡啶络合物，将可见光的能量引导到有机分子中。MacMillan，[3]Yoon，[4]Stephenson，[5]Akita，[6]和其他人[7]的团队最近发表了关于这些配合物催化的可见光促进的C-C键形成反应的开创性工作。胺经常被用作牺牲电子供体，将光激发的RuII和IrIII络合物还原为RuI和IrII络合物。[8]最近，胺也被探索作为这些过程的底物。[9]我们对使用胺作为牺牲供体和底物的可能性很感兴趣，从而使这一过程更经济。我们设想了一类胺，它能够在被光激发的RuII或IrIII络合物氧化时启动下游的不可逆反应。环丙胺被证明在氧化为氮自由基阳离子时，环丙基环发生不可逆的开环。基于这种作用方式，环丙胺已被用于探索生物体系中的胺氧化。[10]到目前为止，环丙胺在有机合成中的应用有限。[11]所有这些应用都集中在分子内的反应上，除了内过氧物的形成。[11A]此外，氮自由基阳离子的产生需要用光敏剂或强氧化剂(如硝酸铈铵)的紫外光，从而限制了底物的范围和/或形成的产物的类型。由于可见光催化已被证明是一种温和的、化学选择性的氧化胺的方法，我们设想可以开发由RuII或IrIII多吡啶络合物催化的环丙胺的新转化(方案1)。本文报道了可见光催化下单环和双环环丙基苯胺与烯烃的分子间[3+2]环加成反应。
Solar energy is clean, abundant, and more importantly, renewable. As such, any reaction that efficiently harvests and converts solar energy into chemical energy is more important than ever as the world turns to its scientists to meet the challenge of environmental sustainability. Visible light (390–750 nm) accounts for 43% of the overall solar spectrum. However, many organic molecules are unable to absorb visible light efficiently, thereby limiting the use of visible light in organic synthesis. A possible solution to this problem involves the use of visible-light photoredox catalysts such as ruthenium [1] or iridium [2] polypyridyl complexes to channel energy from visible light into organic molecules. The groups of MacMillan,[3] Yoon,[4] Stephenson,[5] Akita,[6] and others [7] have recently published seminal works on visible-light-promoted C–C bond-formation reactions catalyzed by these complexes. Amines are often used as a sacrificial electron donor to reduce the photoexcited RuII and IrIII complexes to RuI and IrII complexes.[8] Recently, amines have been also explored as a substrate in these processes.[9] We were intrigued by the potential of using amines as both the sacrificial donor and the substrate, thus making the process more atom economical.We envisioned a class of amines that are capable of initializing a downstream irreversible reaction upon oxidation by the photoexcited RuII or IrIII complexes. Cyclopropylamines have been shown to undergo irreversible opening of the cyclopropyl ring upon their oxidation to the nitrogen radical cations. Based on this mode of action, cyclopropylamines have been used to probe amine oxidation in biological systems.[10] Cyclopropylamines have seen limited use in organic synthesis to date.[11] All these applications focus on intramolecular reactions, except the formation of the endoperoxides.[11a] Furthermore, the generation of nitrogen radical cations requires UV light with a photosensitizer or a strong oxidant (eg, ceric ammonium nitrate), thus limiting the substrate scope and/or the type of the products being formed. Since visible-light photocatalysis has been shown to be a mild and chemoselective method to oxidize amines, we envisioned that new transformations of cyclopropylamines catalyzed by a RuII or IrIII polypyridyl complex could be developed (Scheme 1). Herein we report an intermolecular [3+ 2] cycloaddition of olefins with monoand bicyclic cyclopropylanilines under visible light photocatalysis.
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影响因子：
1.8
作者：
CEKOVIC, Z;SAICIC, R
通讯作者：
SAICIC, R
影响因子：
2.1
作者：
Chang, Meng-Yang;Tai, Hang-Yi;Chen, Yeh-Long
通讯作者：
Chen, Yeh-Long
影响因子：
15
作者：
DELAIVE, PJ;FOREMAN, TK;WHITTEN, DG
通讯作者：
WHITTEN, DG
影响因子：
15
作者：
Ischay, Michael A.;Anzovino, Mary E.;Yoon, Tehshik P.
通讯作者：
Yoon, Tehshik P.
影响因子：
2.4
作者：
Bunce, RA;Herron, DM;Kotturi, SV
通讯作者：
Kotturi, SV