Practical synthesis of pinacolborane for one-pot synthesis of unsymmetrical biaryls via aromatic C-H borylation-cross-coupling sequence

TETRAHEDRON

卷:64

Article

Kikuchi, Takao¹  Nobuta, Yusuke¹  Umeda, Junko¹  Yamamoto, Yasunori¹  Ishiyama, Tatsuo¹  Miyaura, Norio¹ 

[1] Hokkaido Univ, Grad Sch Engn, Div Chem Proc Engn, Sapporo, Hokkaido 0608628, Japan

关键词: pinacolborane;    biaryls;    boron;    C-H activation;    cross-coupling;   

DOI  :  10.1016/j.tet.2008.03.102

来源: Elsevier

【 摘 要 】

A method for practical preparation of pinacolborane from borane-diethylaniline and pinacol was newly developed. Aromatic C-H borylation of arenes with pinacolborane or bis(pinacolato)diboron catalyzed by 1/2[Ir(OMe)(COD)](2)-(4,4'-di-tert-butyl-2,2'-bipyridine) at 25 degrees C in hexane to give arylboronic esters was directly followed by cross-coupling with aromatic bromides at 60 degrees C in the presence of PdCl(2)(dppf) (3.0 mol %) and K(3)PO(4) in DMF. This one-pot, two-step procedure provided a variety of unsymmetrical biaryls in high yields. (C) 2008 Elsevier Ltd. All rights reserved.

【 授权许可】

Free