directing group in C–H bond-functionalization reactions, reductive removal of this directing group is not straightforward. Currently available methods are limited to nickel-catalyzed reactions using i PrMgX or hydrosilane as a reductant, leaving the functional group compatibility issue to be solved. Herein, we report rhodium-catalyzed reductivecleavage of aryl carbamates using i PrOH as a milder reductant
尽管在 C-H 键官能化反应中广泛使用氨基甲酸酯作为导向基团,但还原去除该导向基团并不简单。目前可用的方法仅限于使用 i PrMgX 或氢硅烷作为还原剂的镍催化反应,留下官能团兼容性问题有待解决。在此,我们报告了使用 i PrOH 作为更温和的还原剂对氨基甲酸芳基酯进行铑催化的还原裂解。
Development and Mechanistic Studies of Iron-Catalyzed Construction of Csp<sup>2</sup>–B Bonds via C–O Bond Activation
Herein we describe an iron-catalyzed borylation of alkenyl and arylcarbamatesthrough the activation of a C–O bond. This protocol exhibits high efficiency, a broad substrate scope, and the late-stage borylation of biorelevant compounds, thus providing potential applications in medicinal chemistry. Moreover, this method enables orthogonal transformations of phenol derivatives and also offers good opportunities
在本文中,我们描述了通过C-O键的活化,铁催化的烯基和芳基氨基甲酸酯的硼酸酯化反应。该方案显示出高效率,广泛的底物范围以及生物相关化合物的后期硼化,因此在药物化学中提供了潜在的应用。而且,该方法能够使酚衍生物进行正交转化,并且还为合成多取代的芳烃提供了良好的机会。初步的机理研究表明,通过自由基途径的Fe II / Fe III催化循环可能与反应有关。
Rhodium-catalyzed cross-coupling of aryl carbamates with arylboron reagents
A new method has been developed for the rhodium-catalyzedcross-coupling of aryl carbamates with organoboron reagents. The use of an NHC ligand bearing a 2-adamantyl group, i.e., I(2-Ad), is essential to the success of the reaction. The reaction involves the rhodium-mediated activation of the relatively inert C(aryl)-O bond of aryl carbamates.
N‐diethylarylamide using CIPE‐assisted α‐silyl carbanions (CIPE=complex‐inducedproximityeffect) has been developed using a simple reagent combination of LDA (lithium diisopropylamide) and chlorosilane. A study of the mechanism, and the application of the procedure to an anionic Snieckus–Fries rearrangement for a highly efficient synthesis of the potent phosphatidylinositol 3‐kinase (PI3K) inhibitor LY294002
Amide-Directed Ru-Catalyzed Hydrodemethoxylation of <i>ortho</i>-Methoxy-Benzamides and -Naphthamides: A D<i>o</i>M Reaction Counterpart
作者:Yigang Zhao、Victor Snieckus
DOI:10.1021/acs.orglett.8b00755
日期:2018.5.18
A new ruthenium-catalyzed hydrodemethoxylation of ortho-methoxy-benzamides and -naphthamides involving amide-directed C–OMe bond activation and hydride reduction is disclosed. The reaction is general, proceeding under RuH2(CO)(PPh3)3 catalysis using either triethylsilane (Et3SiH) or diisobutylaluminum hydride (DIBAL-H) as the reductant. The corresponding C–N hydrodeamination reaction is also briefly