Palladium-Catalyzed Arylation of α,α-Disubstituted Arylmethanols via Cleavage of a C−C or a C−H Bond To Give Biaryls
作者:Yoshito Terao、Hiroyuki Wakui、Michiyo Nomoto、Tetsuya Satoh、Masahiro Miura、Masakatsu Nomura
DOI:10.1021/jo0344034
日期:2003.6.1
The palladium-catalyzed arylation of alpha,alpha-disubstituted arylmethanols with aryl halides proceeds not only via C-H bond cleavage at the ortho-position, but also via cleavage of the sp(2)-sp(3) C-C bond with the liberation of ketones (beta-carbon elimination) to give the corresponding biaryls. Both reactions appear to occur through common arylpalladium(II) alcoholate intermediates. The results
钯催化的α,α-二取代的芳基甲醇与芳基卤化物的芳基化反应不仅通过邻位的CH键裂解,还通过sp(2)-sp(3)CC键的裂解以及酮的释放而进行(β-碳消除)得到相应的联芳基。这两个反应似乎都是通过常见的芳基钯(II)醇盐中间体发生的。报道了关于在芳基化中优先裂解CC或CH键的系统研究的结果。在重要发现中,由于空间原因,甚至可以从芳基(二苯基)甲醇中选择性除去邻位取代的芳基。因此,通过用芳基溴化物和氯化物处理相应的芳基(二苯基或二甲基)甲醇,可以有效地生产具有邻取代基的各种联芳基。