The Ruthenium-Catalyzed Reduction and Reductive N-Alkylation of Secondary Amides with Hydrosilanes: Practical Synthesis of Secondary and Tertiary Amines by Judicious Choice of Hydrosilanes
作者:Shiori Hanada、Toshiki Ishida、Yukihiro Motoyama、Hideo Nagashima
DOI:10.1021/jo070591c
日期:2007.9.1
(1) catalyzes the reaction of secondary amides with hydrosilanes, yielding a mixture of secondary amines, tertiary amines, and silyl enamines. Production of secondary amines with complete selectivity is achieved by the use of higher concentration of the catalyst (3 mol %) and the use of bifunctional hydrosilanes such as 1,1,3,3-tetramethyldisiloxane. Acidic workup of the reaction mixture affords the
甲羰基三钌簇,(μ 3,η 2,η 3,η 5 -acenaphthylene)的Ru 3(CO)7(1)催化仲酰胺与氢硅烷的反应,生成仲胺,叔胺和甲硅烷基烯胺的混合物。通过使用较高浓度的催化剂(3 mol%)和使用双官能氢硅烷(例如1,1,3,3-四甲基二硅氧烷),可以实现具有完全选择性的仲胺的生产。对反应混合物进行酸性处理后,可得到相应的铵盐,可用碱进行处理,从而为分离高纯度仲胺提供了一种简便的方法。相反,通过使用较低浓度的催化剂(1mol%)和聚合氢硅氧烷(PMHS)作为还原剂,以高选择性形成叔胺。用PMHS还原将钌催化剂和有机副产物封装到不溶性有机硅树脂中。这两个反应歧管适用于各种仲酰胺,并且实用性在于该程序提供所需的仲胺或叔胺作为单一产物。产品仅被少量的钌和硅残留物污染。基于产物和观察到的副产物以及NMR研究,还描述了反应的机理方案。