Alkynyl Moiety for Triggering 1,2‐Metallate Shifts: Enantiospecific sp
<sup>2</sup>
–sp
<sup>3</sup>
Coupling of Boronic Esters with
<i>p</i>
‐Arylacetylenes
作者:Venkataraman Ganesh、Marcin Odachowski、Varinder K. Aggarwal
DOI:10.1002/anie.201703894
日期:2017.8.7
The enantiospecific coupling of secondary and tertiary boronic esters to aromatics has been investigated. Using p-lithiated phenylacetylenes and a range of boronic esters coupling has been achieved by the addition of N-bromosuccinimide (NBS). The alkyne functionality of the intermediate boronate complex reacts with NBS triggering the 1,2-migration of the group on boron to carbon giving a dearomatized
已经研究了仲和叔硼酸酯与芳族化合物的对映体特异性偶联。通过添加N-溴代琥珀酰亚胺(NBS),已使用对位锂化的苯乙炔和一系列硼酸酯实现了偶联。中间体硼酸酯配合物的炔官能团与NBS反应,触发硼上的基团从1,2-迁移到碳上,从而得到脱芳基化的溴丙二烯中间体。此时,新戊基硼酸酯会发生消除和重新芳构化,从而产生偶联产物。然而,使用频哪醇硼酸酯,硼部分迁移至相邻的碳,导致形成结合有邻硼的偶联产物。通过炔烃和硼酸酯官能团的正交转化证明了掺入硼的产物的合成效用。