Asymmetric 1,4-Addition of
Arylboronic Acids to α,β-Unsaturated Esters Catalyzed
by Dicationic Palladium(II)-Chiraphos Complex for Short-Step Synthesis
of SmithKline Beecham’s Endothelin Receptor Antagonist
作者:Norio Miyaura、Takashi Nishikata、Shunsuke Kiyomura、Yasunori Yamamoto
DOI:10.1055/s-2008-1078259
日期:——
An asymmetric 1,4-addition of arylboronic acids to RCH=CHCO2Ar (Ar = Ph or 4-acetylphenyl) was carried out at 50 ËC in aqueous acetone in the presence of [Pd(chiraphos)(PhCN)2](SbF6)2. The reaction gave optically active β-aryl esters in up to 98% ee. The protocol provided a simple access to an endothelin receptor antagonist reported by SmithKline Beecham.
在[Pd(chiraphos)(PhCN)2](SbF6)2 的存在下,在 50 ℃ 的丙酮水溶液中进行了芳基硼酸与 RCH=CHCO2Ar (Ar = Ph 或 4-乙酰苯基)的不对称 1,4-加成反应。反应生成了具有光学活性的δ-芳基酯,ee值高达 98%。该方案为 SmithKline Beecham 公司报告的内皮素受体拮抗剂提供了一个简单的途径。