Copper‐Catalyzed Azide–Ynamide Cyclization to Generate α‐Imino Copper Carbenes: Divergent and Enantioselective Access to Polycyclic N‐Heterocycles
作者:Xin Liu、Ze‐Shu Wang、Tong‐Yi Zhai、Chen Luo、Yi‐Ping Zhang、Yang‐Bo Chen、Chao Deng、Rai‐Shung Liu、Long‐Wu Ye
DOI:10.1002/anie.202007206
日期:2020.10.5
Here an efficient copper‐catalyzed cascade cyclization of azide‐ynamides via α‐imino copper carbene intermediates is reported, representing the first generation of α‐imino copper carbenes from alkynes. This protocol enables the practical and divergent synthesis of an array of polycyclic N‐heterocycles in generally good to excellent yields with broad substrate scope and excellent diastereoselectivities
Generation of Donor/Donor Copper Carbenes through Copper-Catalyzed Diyne Cyclization: Enantioselective and Divergent Synthesis of Chiral Polycyclic Pyrroles
作者:Feng-Lin Hong、Ze-Shu Wang、Dong-Dong Wei、Tong-Yi Zhai、Guo-Cheng Deng、Xin Lu、Rai-Shung Liu、Long-Wu Ye
DOI:10.1021/jacs.9b09303
日期:2019.10.23
yields with wide substratescope and excellent enantioselectivities (up to 97:3 e.r.). Importantly, this protocol represents the first copper-catalyzed asymmetric diyne cyclization. Moreover, mechanisticstudies revealed that the generation of donor/donor copper carbenes is presumably involved in this 1,5-diyne cyclization, which is distinctively different from the related gold catalysis, and thus it constitutes
be readily constructed by using this protocol. This copper-catalyzed oxidative process proceeds through an alkyne oxidation, carbene/alkynemetathesis, and donor–donor carbene oxidation sequence. The use of readily available substrates, high flexibility, a simple procedure, and mild reaction conditions render the procedure a viable alternative for the preparation of functionalized γ-lactams.
Gold(I)‐Catalyzed and PTSA‐Promoted Cycloisomerization of Ynamides to Access Pyrrole Substituted α,β‐Unsaturated Ketones**
作者:Shivani Choudhary、Gayyur、Nayan Ghosh
DOI:10.1002/ejoc.202201223
日期:2023.1.24
In this work, a new ynamide scaffold has been designed, synthesized and later applied in a gold-catalyzed cycloisomerization reaction to access pyrrole containing α,β-unsaturated ketones in low-to-moderate yields. Interestingly, the trans product has been obtained as a major isomer.