Ni<sup>0</sup>-catalyzed Direct Amination of Anisoles Involving the Cleavage of Carbon–Oxygen Bonds
作者:Mamoru Tobisu、Toshiaki Shimasaki、Naoto Chatani
DOI:10.1246/cl.2009.710
日期:2009.7.5
Ni 0 -catalyzed cross-coupling of aryl methyl ethers with amines is described. The use of an N-heterocyclic carbene as a ligand and NaOt-Bu as a base promotes the amination of anisole derivatives via the cleavage of normally unreactive aryl carbon-oxygenbonds.
描述了 Ni 0 催化的芳基甲基醚与胺的交叉偶联。使用 N-杂环卡宾作为配体和 NaOt-Bu 作为碱促进苯甲醚衍生物通过通常不活泼的芳基碳-氧键的断裂进行胺化。
Cross-Coupling of Organolithium with Ethers or Aryl Ammonium Salts by C−O or C−N Bond Cleavage
and/or alkyllithium species reacted smoothly with aryl and/or benzyl ethers with cleavage of the inert C−O bond to afford cross‐coupled products, catalyzed by commercially available [Ni(cod)2] (cod=1,5‐cyclooctadiene) catalysts with N‐heterocyclic carbene (NHC) ligands. Furthermore, the couplingreaction between the aryllithium compounds and aryl ammonium salts proceeded under mild conditions with C−N
An ethericNegishicoupling: The first cross‐coupling reaction between aryl alkyl ethers and dianion‐type zincate reagents to afford biaryl compounds through selective cleavage of the ethericC(sp2)O bond was developed. Dianion‐type zincates showed excellent reactivity toward the aromatic ethersundermildconditions, with good functional group compatibility (see scheme).
Lewis Acid Assisted Nickel‐Catalyzed Cross‐Coupling of Aryl Methyl Ethers by C−O Bond‐Cleaving Alkylation: Prevention of Undesired β‐Hydride Elimination
In the presence of trialkylaluminum reagents, diverse aryl methyl ethers can be transformed into valuable products by C−O bond‐cleaving alkylation, for the first time without the limiting β‐hydride elimination. This new nickel‐catalyzed dealkoxylative alkylation method enables powerful orthogonal synthetic strategies for the transformation of a variety of naturally occurring and easily accessible anisole