cobalt‐catalyzed arylation of benzyl chlorides has been developed in order to form functionalized diarylmethanes. A variety of reactive groups either on the aryl or the benzyl halide was employed. This represents the first cobalt‐catalyzed reductive cross‐coupling which does not require any ligand and pyridine. A reaction pathway is proposed involving a radical benzyl species.
Preparation of Functionalized Organoindium Reagents by Means of Magnesium Insertion into Organic Halides in the Presence of InCl<sub>3</sub>at Room Temperature
procedure for the direct preparation of triorganoindium reagents from organichalides by means of magnesium insertion in the presence of InCl3 and LiCl is reported (see scheme). The organoindium reagents are obtained in good yields from functionalized aryl, heteroaryl, and alkyl bromides and benzyl chlorides at 25 °C in THF within 4 h. Moreover, the resulting organoindium reagents could be efficiently
Pd-catalyzed chemoselective threefold cross-coupling of triarylbismuths with benzylic bromides
作者:Maddali L. N. Rao、Ritesh J. Dhanorkar
DOI:10.1039/c3ra40413g
日期:——
for the chemoselective cross-coupling of functionalized benzylic bromides with triarylbismuthreagents. Under the established conditions, catalyzed by palladium in the presence of K3PO4 base in DMA at 90 °C for 1 h, the threefoldarylations using triarylbismuthreagents proceeded smoothly with electronically diverse benzylic bromides. All the coupling reactions furnished the corresponding functionalized
对于功能化的苄基溴化物与三芳基铋试剂的化学选择性交叉偶联,证明了一种有效的钯催化方案。在既定条件下,钯在DMA中在90°C下在DMA中存在K 3 PO 4碱的条件下催化1 h,使用三芳基铋试剂进行的三重芳基化反应可通过电子形式多样的苄基溴顺利进行。所有偶联反应均以高收率提供了相应的官能化二芳基甲烷。
Direct Method for Carbon-Carbon Bond Formation: The Functional Group Tolerant Cobalt-Catalyzed Alkylation of Aryl Halides
作者:Muriel Amatore、Corinne Gosmini
DOI:10.1002/chem.201000178
日期:2010.5.25
cobalt‐catalyzedalkylation of aryl halides has been developed that proceeds smoothly in the presence of phosphanes or bipyridines as ligands with a variety of alkylhalides, including challenging alkyl electrophiles bearing β‐hydrogen atoms (see scheme). Sensitive functional groups are tolerated on both coupling partners, thus, significantly extending the general scope of transition‐metal‐catalyzed
Cross-couplings between benzylic and aryl halides “on water”: synthesis of diarylmethanes
作者:Christophe Duplais、Arkady Krasovskiy、Alina Wattenberg、Bruce H. Lipshutz
DOI:10.1039/b922280d
日期:——
A remarkably simple entry to unsymmetrical diarylmethanes has been developed that relies on an in situ organozinc-mediated, palladium-catalyzed cross-coupling. Thus, by mixing a benzyl and aryl halide together in the presence of Zn metal and a Pd catalyst, diarylmethanes are formed at room temperature without assistance by a surfactant; hence, "on water".