Arylethyne Bromoboration-Negishi Coupling Route to<i>E</i>- or<i>Z</i>-Aryl-Substituted Trisubstituted Alkenes of ≥98% Isomeric Purity. New Horizon in the Highly Selective Synthesis of Trisubstituted Alkenes
作者:Chao Wang、Zhaoqing Xu、Tomas Tobrman、Ei-ichi Negishi
DOI:10.1002/adsc.200900766
日期:2010.3.8
to proceed satisfactorily through (1) the use of highly catalytically active bis(tri‐tert‐butylphosphine)palladium or dichloro[N,N‐bis‐(2,6‐diisopropylphenyl)imidazol‐2‐yl](m‐chloropyridine)palladium and (2) conversion of the dibromoboryl group to the (pinacol)boryl group. Thus, a wide variety of carbon groups can be used to substitute bromine in ≥98% stereo‐ and regioselectivity, while suppressing
的迄今前所未有钯-催化的交叉偶联(ż)-β-溴-β-arylethenylboranes可以使通过(1)使用高催化活性的双(三-令人满意地进行叔丁基膦)钯或二氯[ Ñ , N-双-(2,6-二异丙基苯基)咪唑-2-基]( m-氯吡啶)钯和(2)二溴硼基转化为(频哪醇)硼基。因此,多种碳基团可用于以≥98% 的立体选择性和区域选择性取代溴,同时抑制其他占主导地位的 β-脱溴。与基于烷基乙炔的方案一起,炔烃溴硼化-Negishi 偶联串联工艺已成为最广泛适用和高度选择性的三取代烯烃路线,包括那些难以获得的烯烃。