Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 76100, Israel.
J Am Chem Soc. 2010 Dec 1;132(47):16756-8. doi: 10.1021/ja1080019. Epub 2010 Nov 4.
The selective, direct hydrogenation of amides to the corresponding alcohols and amines with cleavage of the C-N bond was discovered. The expected products of C-O cleavage are not formed (except as traces in the case of anilides). The reaction proceeds under mild pressure and neutral, homogeneous conditions using a dearomatized, bipyridyl-based PNN Ru(II) pincer complex as a catalyst. The postulated mechanism involves metal-ligand cooperation by aromatization-dearomatization of the heteroaromatic pincer core and does not involve hydrolytic cleavage of the amide. The simplicity, generality, and efficiency of this environmentally benign process make it attractive for the direct transformations of amides to alcohols and amines in good to excellent yields.
酰胺选择性、直接氢化生成相应的醇和胺,同时 C-N 键断裂。预期的 C-O 键断裂产物并未形成(除了酰苯胺的痕量产物)。反应在温和的压力和中性均相条件下进行,使用去芳构化的双吡啶基 PNN Ru(II) 夹式配合物作为催化剂。所提出的反应机制涉及杂芳环夹式核的芳构化-去芳构化的金属-配体协同作用,并且不涉及酰胺的水解断裂。该环境友好过程的简单性、通用性和高效性使其在酰胺直接转化为醇和胺的反应中具有吸引力,产率良好至优秀。