作者:Manfred Schlosser、Frédéric Leroux、Joanna Gorecka
DOI:10.1055/s-2004-815926
日期:——
Starting from the inexpensive 2,2-difluoro-1,3-benzodioxole or its 5-bromo derivative, two new atropisomeric bisphosphines have been prepared which, after racemate resolution, exhibit attractive features as ligands for enantioselective catalysts. The key step in their synthesis is a low temperature Ullmann reaction. An improved protocol secures coupling yields of 70-80%.
从廉价的2,2-二氟-1,3-苯并二氧杂环戊烯或其5-溴衍生物开始,制备了两种新的阻转异构双膦,在外消旋体拆分后,它们作为对映选择性催化剂的配体表现出有吸引力的特征。其合成的关键步骤是低温乌尔曼反应。改进的协议可确保 70-80% 的耦合产率。