Synthesis of (−)‐Dihydroraputindole D by Enantioselective Benzoylation of a 1,3‐Diol Intermediate
作者:Marvin Fresia、Mario Kock、Thomas Lindel
DOI:10.1002/chem.202002579
日期:2020.10.6
The enantioselective synthesis of (−)‐dihydroraputindole D is reported. The key step is the desymmetrizing benzoylation of a prochiral 1,3‐diol employing Trost′s ProPhenol catalyst system, which has been applied for the first time to a cyclic molecule carrying geminal hydroxymethyl groups. The cyclopenta[f]indoline system was assembled by Au(I)‐catalyzed cyclization of an alkynylated indoline precursor
据报道(-)-dihydroraputindole D的对映选择性合成。关键步骤是使用Trost的ProPhenol催化剂体系对前手性1,3-二醇进行脱对称化苯甲酰化,该体系已首次应用于带有双羟甲基基团的环状分子。通过Au(I)催化的炔基化吲哚啉前体的环化反应,组装了环戊四烯[ f ]吲哚啉系统。从二羟基丙酮开始,分17步获得(-)-Dihydroraputindole D,总收率8%。结合ECD光谱的量子化学计算,我们的合成使我们能够确定Rutaceous植物Raputia simulans的天然产物(+)-raputindole D的绝对构型(5 S,7 R)。