more economically attractive but usually much more difficult as substrates in metal-mediated couplings than the corresponding bromides and iodides. A catalyst prepared from a bulky (biaryl)diphenyl phosphane and a common ruthenium source (1:1) mediates selective direct monoarylations of arenes bearing 2-pyridyl and related ortho-directing groups in good yields. Sequential arylations to heterodiarylated
Cobalt-Catalyzed C−H Functionalizations by Imidate Assistance with Aryl and Alkyl Chlorides
作者:Ruhuai Mei、Lutz Ackermann
DOI:10.1002/adsc.201600384
日期:2016.7.28
inexpensive cobalt(II) acetylacetonate [Co(acac)2] and an N‐heterocyclic carbene (NHC) ligand enabled versatile C−H arylations by oxazoline assistance. The broadly applicable, low‐valent cobalt catalyst displayed a wide substrate scope, and even proved applicable to challenging C−H alkylations with β‐hydrogen‐containing primary and secondary alkyl chlorides. The power of the cobalt‐catalyzed C−H arylation