Hydrosilylative Reduction of Tertiary Amides to Amines Catalyzed by
<i>N</i>
‐(Phosphinoaryl)anilido Complexes of Iron and Cobalt
作者:Dylan J. Hale、Luke J. Murphy、Robert McDonald、Michael J. Ferguson、Laura Turculet
DOI:10.1002/cctc.201900550
日期:2019.8.21
Fe(II) and Co(II) complexes supported by the monoanionic P,N‐ligand N‐(2‐dicyclohexylphosphinophenyl)‐2,6‐diisopropylanilide are described. A three‐coordinate (P,N)Fe‐hexamethyldisilazide complex (2), and four‐coordinate (P,N)Fe‐ (3‐Fe) and (P,N)Co‐alkyl (3‐Co) complexes were evaluated as pre‐catalysts for the hydrosilylative reduction of amides with PhSiH3 (5 mol % pre‐catalyst, 1 equiv. PhSiH3, 80 °C
描述了由单阴离子P,N-配体N-(2-二环己基膦基苯基)-2-,6-二异丙基苯胺支持的低配位Fe(II)和Co(II)配合物的合成和结构表征。评估了三坐标(P,N)Fe-六甲基二硅叠氮化物配合物(2)和四坐标(P,N)Fe-(3-Fe)和(P,N)Co-烷基(3-Co)配合物作为预催化剂用于与PhSiH的hydrosilylative还原酰胺3(5mol%的预催化剂,1当量PhSiH 3,80℃,1-24小时)。的铁络合物2被证明是更广泛有效用于多种叔酰胺底物的减少,以及被证明介导的还原Ñ,N-二苄基苯甲酰胺的负载量为1 mol%,以在1 h(80°C)下几乎定量地形成三苄基胺。配合物2还证明可在环境条件下(5 mol%Fe,24 h)对叔酰胺进行氢化硅烷化,这是由Fe催化剂介导的无需光化学活化的室温酰胺氢化硅烷化的独特实例。鉴于酰胺还原方案在合成中的广泛应用,开发在温和条件下运行的高效铁基催化剂是重要的目标。