Copper‐Catalyzed Asymmetric Diyne Cyclization via [1,2]‐Stevens‐Type Rearrangement for the Synthesis of Chiral Chromeno[3,4‐c]pyrroles

• Published in: Angewandte Chemie International Edition Vol. 61; no. 7; pp. e202115554 - n/a
• Main Authors: Hong, Feng‐Lin, Shi, Chong‐Yang, Hong, Pan, Zhai, Tong‐Yi, Zhu, Xin‐Qi, Lu, Xin, Ye, Long‐Wu
• Format: Journal Article
• Language: English
• Published: WEINHEIM Wiley 07.02.2022
• Subjects: Alkynes; Asymmetric catalysis; Chemistry; Chemistry, Multidisciplinary; Heterocycles; Metal carbenes; Physical Sciences; Rearrangement; Science & Technology; Heterocycles; ORGANIC-SYNTHESIS; CARBENE; INSERTION; GOLD CATALYSIS; FORMAL STEVENS SHIFT; ALKYNYLIODONIUM SALTS; YLIDES; Asymmetric catalysis; YNAMIDES; ETHERS; Metal carbenes; ACCESS; Alkynes; Rearrangement
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202115554

Here, we report a copper‐catalyzed asymmetric cascade cyclization/[1,2]‐Stevens‐type rearrangement via a non‐diazo approach, leading to the practical and atom‐economic assembly of various valuable chiral chromeno[3,4‐c]pyrroles bearing a quaternary carbon stereocenter in generally moderate to good yields with wide substrate scope and excellent enantioselectivities (up to 99 % ee). Importantly, this protocol not only represents the first example of catalytic asymmetric [1,2]‐Stevens‐type rearrangement based on alkynes but also constitutes the first asymmetric formal carbene insertion into the Si−O bond. A copper‐catalyzed asymmetric cascade cyclization/[1,2]‐Stevens‐type rearrangement is disclosed, affording valuable chiral chromeno[3,4‐c]pyrroles bearing a quaternary carbon stereocenter in generally moderate to good yields with excellent enantioselectivities. Importantly, this protocol represents the first catalytic asymmetric [1,2]‐Stevens‐type rearrangement based on alkynes and the first asymmetric formal carbene insertion into the Si−O bond.