ol5032365_si_002.cif (24.89 kB)
Copper-Mediated Dimerization to Access 3a,3a′-Bispyrrolidinoindoline: Diastereoselective Synthesis of (+)-WIN 64821 and (−)-Ditryptophenaline
datasetposted on 2015-01-16, 00:00 authored by Kangjiang Liang, Xu Deng, Xiaogang Tong, Dashan Li, Ming Ding, Ankun Zhou, Chengfeng Xia
A copper-mediated cyclization and dimerization of tryptamine or tryptophan was developed to generate a C2-symmetry C3(sp3)–C3(sp3) bridge with two contiguous stereogenic quaternary carbons in one step. Impressively, the ratio between exo and endo cyclization products varies when different protecting groups of Nb are utilized. This dimerization reaction could be conducted in gram scale. With this dimerization method, both endocyclotryptophan (+)-WIN 64821 and exocyclotryptophan (−)-ditryptophenaline were synthesized in 5 steps.