Successive Iodine−Magnesium or −Copper Exchange Reactions for the Selective Functionalization of Polyhalogenated Aromatics
摘要:
The presence of an electron-withdrawing group or chelating group was found to direct the halogen-copper and halogen-magnesium exchange with various di- or trihalogenated aromatics. Starting with a triiodobenzoate derivative, a range of tetraacylated benzenes could be prepared and used for a short synthesis of benzodiazines.
Preparation of Functionalized Organomanganese(II) Reagents by Direct Insertion of Manganese to Aromatic and Benzylic Halides
作者:Zhihua Peng、Paul Knochel
DOI:10.1021/ol201109g
日期:2011.6.17
arylmanganese compounds were prepared using commercial manganese powder in the presence of LiCl and catalyticamounts of both 2.5% InCl3 and 2.5% PbCl2 (THF, 0–50 °C). In addition, benzylic manganese reagents are obtained at 25 °C in ca. 70–80% yield (in the absence of LiCl) using commercial manganese powder and catalyticamounts of 2.5% InCl3 and 2.5% PbCl2. The resulting organomanganese reagents undergo
A wide range of directing groups (ester, ketone, acetate, aryl sulfonate, triazene, carbamate) allow the regioselective directed ortho insertion (DoI) of zinc in the presence of LiCl leading to polyfunctional aryl and heteroaryl zinc reagents.
A Cobalt-Catalyzed Sulfonate/Copper Exchange for the Preparation of Highly Functionalized Electron-Deficient Aryl Copper Reagents
作者:Christoph J. Rohbogner、Coura R. Diène、Tobias J. Korn、Paul Knochel
DOI:10.1002/anie.200905379
日期:2010.3.1
Organocopper reagents from phenols: A new cobalt‐catalyzed arylsulfonate/copperexchange reaction allows the synthesis of highlyfunctionalizedarylcopperreagents from sulfonates bearing electron‐deficient substituents under mild conditions (25–45 °C, 1–6 h; see example). Sensitive functional groups, such as aldehydes, esters, and nitriles, are well‐tolerated.
Preparation and Reactions of Functionalized Organocopper Reagents
作者:Paul Knochel、Xiaoyin Yang
DOI:10.1055/s-2006-942496
日期:2006.8
Functionalized organocopper reagents have been prepared via an iodine-copper exchange by the reaction of aryl or alkenyl iodides with a sterically hindered cuprate reagent, lithium dineophylcuprate [(Me 2 PhCCH 2 ) 2 CuLi]. The resulting copperreagents react readily with various electrophiles leading to polyfunctionalized molecules. This method represents a unique protocol for the preparation of aryl-