L-脯氨酸衍生物的制备及其在苯乙酮类化合物立体选择性还原反应中的应用

L-proline derivatives:preparation and application in enantioselective reduction of acetophenone-type substrates

目的设计制备手性脯氨酸衍生物,考察其在不对称催化反应中的应用。方法以L-脯氨酸和L-哌啶羧酸为起始原料,经酯化、氨基保护及进一步衍生化得到脯氨醇类似物,通过核磁共振谱、高分辨质谱等手段对其结构进行确证。所得手性化合物与三甲基环三硼氧烷作用得到催化剂。结果与结论制备了2个含有环丙烷基团的手性氨基醇类化合物,与三甲基环三硼氧烷作用得到催化剂。在该手性催化剂作用下,以硼烷二甲硫醚为还原剂,在50℃条件下与苯乙酮类化合物发生还原反应,产物收率最高可达99%,产物的对映体过量最高达88%。所得到的氨基醇类手性配体较含二苯基的配体在苯乙酮类化合物的立体选择性还原反应中具有更好的表现。

Enantioselective reduction of prochiral ketones is one of the most efficient methods for the preparation of optically active secondary alcohols.In this paper,two aminoalcohols were prepared,characterized and applied in the enantioselective CBS reduction of acetophenone-type substrates.Up to 99% isolated yield and up to 88% ee were observed.The current study will offer a new idea on the design of new chiral catalysts for enantioselective reduction of prochiral ketones.