Exceptional selectivity in cyclopropanation reactions catalyzed by chiral cobalt(II)-porphyrin catalysts.
Exceptional selectivity in cyclopropanation reactions catalyzed by chiral cobalt(II)-porphyrin catalysts.
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DOI：
10.1002/anie.200804940
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发表时间：
2009
影响因子：
16.6
通讯作者：
Doyle, Michael P.
中科院分区：
文献类型：
--
作者：
Doyle, Michael P.
对高立体选择性烯烃加成反应的研究有着悠久而持续的历史，使用重氮乙酸酯的烯烃环丙烷化反应是这一研究的核心内容。[1]催化方法学，特别是那些建立在具有手性配体的过渡金属平台上的催化方法学，已经刺激了今天提供接近立体异构体检测极限的非对映体控制和对映体选择性的发展。[2]从含手性Salen配体的铜催化[3]到手性半咕啉[4]和双恶唑啉[5]配体，重氮乙酸酯的对映体控制分子间加成反应得到了迅速的发展。手性二铑（II）羧酰胺化物在分子内反应中发挥作用[6]，尽管已经报道了许多其他过渡金属和手性配体的结果，在最近出现钴（II）之前，没有一种催化剂能够超过铜和铑催化剂提供的整体立体控制在对映选择性分子间环丙烷化反应中的最初成功之一是由中村及其同事报道的手性卟啉。钴（II）的dioximato络合物衍生自樟脑[7]，但在催化剂均匀性的困难与手性dioximato配体抑制进一步的活动。随后，Katsuki [8] Yamada [9]和同事报道了手性钴（III）salen络合物的立体控制环丙烷化反应的有趣结果;[8]然而，这些催化剂至少缺少一个关键因素（产率，非对映选择性或对映选择性）。尽管铜和铑催化剂都促进简单和共轭烯烃的加成，但不促进不饱和酯、腈和酮的加成，钴催化剂甚至对不饱和酯和腈也显示出活性。将钴催化更进一步，Zhang及其同事将钴（II）与手性卟啉结合，生产出具有独特反应性和卓越选择性的催化剂。[10]在最近的研究中，他报道了α-硝基重氮乙酸酯在制备Z-环丙烷中的应用，收率高，具有出色的非对映体和对映体选择性。[第十一届]
The search for highly stereoselective olefin addition reactions has a long and continuing history, and cyclopropanation reactions of olefins using diazoacetates are core elements in this quest.[1] Catalytic methodologies, especially those built upon a platform of transition metals having chiral ligands, have stimulated developments that today offer diastereocontrol and enantioselectivities that approach the limits of stereoisomer detection.[2] Beginning with copper catalysis having chiral salen ligands [3] and progressing to chiral semicorrin [4] and bis-oxazoline [5] ligands, rapid advances were made in enantiocontroled intermolecular addition reactions of diazoacetates. Chiral dirhodium (II) carboxamidates fulfilled a role in intramolecular reactions [6] and, although results from many other transition metals and chiral ligands have been reported, none have surpassed the overall stereocontrol provided by copper and dirhodium catalysts until the recent emergence of cobalt (II) porphyrins.One of the first successes in enantioselective intermolecular cyclopropanation reactions was a report by Nakamura and coworkers of a chiral cobalt (II) dioximato complex derived from camphor,[7] but difficulties in catalyst homogeneity with chiral dioximato ligands inhibited further activities. Subsequently, Katsuki,[8] Yamada,[9] and coworkers reported intriguing results in stereocontrolled cyclopropanation reactions with chiral cobalt (III) salen complexes;[8] however, at least one of the key ingredients for a breakthrough (yield, diastereoselectivity, or enantioselectivity) was missing with these catalysts. Whereas both copper and dirhodium catalysts promote additions to simple and conjugated olefins, but not unsaturated esters, nitriles, and ketones, cobalt catalysts showed activity even with unsaturated esters and nitriles. Taking cobalt catalysis one step further, Zhang and coworkers have combined cobalt (II) with chiral porphyrins to produce catalysts that exhibit unique reactivities and exceptional selectivities.[10] In this recent manifestation he has reported applications with α-nitro-diazoacetates to prepare Z-cyclopropanes in high yield with exceptional diastereo-and enantioselectivity.[11]
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影响因子：
2.8
作者：
MAXWELL, JL;OMALLEY, S;KODADEK, T
通讯作者：
KODADEK, T
影响因子：
3.6
作者：
Chen, Ying;Zhang, X. Peter
通讯作者：
Zhang, X. Peter
影响因子：
15
作者：
Chen, Ying;Ruppel, Joshua V.;Zhang, X. Peter
通讯作者：
Zhang, X. Peter
影响因子：
4
作者：
Ikeno, T;Sato, M;Yamada, T
通讯作者：
Yamada, T
影响因子：
5.2
作者：
Ruppel, Joshua V.;Jones, Jess E.;Zhang, X. Peter
通讯作者：
Zhang, X. Peter