Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710062, PR China.
Chemistry. 2013 Mar 18;19(12):4021-9. doi: 10.1002/chem.201204194. Epub 2013 Feb 10.
Reductive amination of various ketones and aldehydes by transfer hydrogenation under aqueous conditions has been developed, by using cyclometallated iridium complexes as catalysts and formate as hydrogen source. The pH value of the solution is shown to be critical for a high catalytic chemoselectivity and activity, with the best pH value being 4.8. In comparison with that in organic solvents, the reductive amination in an aqueous phase is faster, and the molar ratio of the substrate to the catalyst (S/C) can be set as high as 1×10(5) , the highest S/C value ever reported in reductive amination reactions. The catalyst is easy to access and the reaction is operationally simple, allowing a wide range of ketones and aldehydes to react with various amines in high yields. The protocol provides a practical and environmental friendly new method for the synthesis of amine compounds.
发展了在水相条件下通过转移氢化用环金属铱配合物作为催化剂和甲酸盐作为氢源还原胺化各种酮和醛。结果表明，溶液的 pH 值对于高催化化学选择性和活性是至关重要的，最佳 pH 值为 4.8。与在有机溶剂中的还原胺化相比，水相中的还原胺化反应速度更快，并且底物与催化剂的摩尔比（S/C）可以高达 1×10(5)，这是在还原胺化反应中报道的最高 S/C 值。该催化剂易于获得，反应操作简单，允许各种酮和醛与各种胺在高收率下反应。该方案为胺类化合物的合成提供了一种实用且环保的新方法。
