A Catalytic Reactor for the Organocatalyzed Enantioselective Continuous Flow Alkylation of Aldehydes
作者:Riccardo Porta、Maurizio Benaglia、Alessandra Puglisi、Alessandro Mandoli、Andrea Gualandi、Pier Giorgio Cozzi
DOI:10.1002/cssc.201402610
日期:2014.12
organocatalyzed enantioselective alkylation of aldehydes was performed for the first time under continuous flow conditions. By using a packed‐bed reactor filled with readily available supported enantiopure imidazolidinone, different aldehydes were treated with three distinct cationic electrophiles. In the organocatalyzed α‐alkylation of aldehydes with 1,3‐benzodithiolylium tetrafluoroborate, excellent
固定化的无金属催化剂的使用为在流动模式下开发可持续流程提供了独特的可能性。在连续流动条件下,首次进行了具有挑战性的分子间有机催化的醛类对映选择性烷基化反应。通过使用填充有容易获得的对映体纯的咪唑啉酮的填充床反应器,用三种不同的阳离子亲电试剂处理不同的醛。与1,3-苯并二硫代四氟硼酸酯进行醛类的有机催化醛的α-烷基化反应时,具有优异的对映选择性,在某些情况下甚至比在烧瓶法中获得的对映选择性更好(在25°C时,ee高达95% ),并且生产率高(超过3800) h -1),因此表明催化反应器可以连续生产对映体富集的化合物。用阮内镍提供的对映异构体富集的α-甲基衍生物(活性药物成分和天然产物的关键中间体)处理烷基化产物。