Dehydrogenative Synthesis of 2,2′‐Bipyridyls through Regioselective Pyridine Dimerization
作者:Shuya Yamada、Takeshi Kaneda、Philip Steib、Kei Murakami、Kenichiro Itami
DOI:10.1002/anie.201814701
日期:2019.6.17
reactions. The most streamlined approach for the synthesis of 2,2′‐bipyridyls is the dehydrogenative dimerization of unfunctionalized pyridine. Herein, we report on the palladium‐catalyzed dehydrogenative synthesis of 2,2′‐bipyridyl derivatives. The Pd catalysis effectively works with an AgI salt as the oxidant in the presence of pivalic acid. A variety of pyridines regioselectively react at the C2‐positions
2,2'-联吡啶已被用作金属催化反应中必不可少的配体。合成2,2'-联吡啶的最简化方法是未官能化吡啶的脱氢二聚作用。在这里,我们报道了钯催化的2,2'-联吡啶衍生物的脱氢合成。在新戊酸存在下,Pd催化有效地以Ag I盐为氧化剂。多种吡啶在C2位置发生区域选择性反应。这种二聚方法适用于具有挑战性的底物,例如空间受阻的3-取代的吡啶,其中吡啶在C2位上发生区域选择性反应。该反应使简明的合成3,3'-di取代-2,2'-联吡啶作为一种不发达的配体。