Introduction of a New Class of Ligands for the Metal-Catalyzed Enantioselective Synthesis
作者:Maurus Spescha
DOI:10.1002/hlca.19930760504
日期:1993.8.11
Protected thiosugars were prepared as ligands for the metal-catalyzed enantioselective synthesis. The protecting groups in these ligands were varied to test a proposed new concept for the metal-catalyzed enantioselective synthesis. This new concept centres on the use of a stair-like ligand with a large substituent on one side and a small substitutent on the other rather than the commonly employed ligands
制备保护的硫糖作为金属催化的对映选择性合成的配体。改变这些配体中的保护基,以测试提出的金属催化对映选择性合成的新概念。该新概念集中在使用阶梯状配体,该配体在一侧上具有大的取代基而在另一侧上具有小的取代基,而不是通常使用的具有C 2对称性的配体(见图3)。在这样的配体中,两个取代基应该对前手性底物的配位有主要影响。为了测试该提案中,用下面的取代基取代-3-硫代-α-d呋喃葡萄糖衍生物的合成:1,2- ö异亚丙基-5,6- ø -亚甲基(见24),1,2:5,6-二- Ö异亚丙基(参见2),5,6- Ô亚环己基-1,2- Ö异亚丙基(见23),1,2- Ô亚环己基-5, 6- O-异亚丙基(参见14),1,2:5,6-二-O-环己基(参见13),5,6- O-(金刚烷-2-亚烷基)-1,2- O-异亚丙基(见21),和1,2:5,6-二- ö - (金刚烷-2-亚基)(参见25,表2)。作为异呋喃糖酶的代表,1