Aza-Piancatelli Rearrangement Initiated by Ring Opening of Donor–Acceptor Cyclopropanes
摘要:
The development of a new platform to initiate the cascade rearrangement of furans for the formation of functionalized cyclopentenone building blocks is reported. This methodology allows the creation of congested vicinal stereogenic centers with high diastereoselectivity through a 4 pi-electrocyclization process.
Aza-Piancatelli Rearrangement Initiated by Ring Opening of Donor–Acceptor Cyclopropanes
摘要:
The development of a new platform to initiate the cascade rearrangement of furans for the formation of functionalized cyclopentenone building blocks is reported. This methodology allows the creation of congested vicinal stereogenic centers with high diastereoselectivity through a 4 pi-electrocyclization process.
Ln(III)/Chiral Brønsted Acid Catalyzed Asymmetric Cascade Ring Opening/Aza-Piancatelli Rearrangement of D–A Cyclopropanes
作者:Lei Xu、Qian Yang、Sishi Zhong、Hongxiang Li、Yurong Tang、Yunfei Cai
DOI:10.1021/acs.orglett.0c03413
日期:2020.11.20
The first Lewis acid and chiral Brønsted acid cooperatively catalyzed asymmetric cascade ringopening/aza-Piancatelli rearrangement reaction of furyl-substituted donor–acceptorcyclopropanes is achieved, enabling the construction of functionalized aminocyclopentenones bearing α-quaternary carbon stereocenters in high yields with excellent enantio- and diastereoselectivities under remarkably low catalyst