Issue 19, 2024

Asymmetric synthesis of 1H-pyrazolo[3,4-b]pyridine analogues catalyzed by chiral-at-metal Rh(iii) complexes

Abstract

An efficient asymmetric Friedel–Crafts-type alkylation/cyclization of 5-aminopyrazoles with α,β-unsaturated 2-acyl imidazoles has been developed, affording corresponding pyrazolo[3,4-b]pyridine analogues in 81–98% yield with 85–99% enantioselectivity. Remarkably, this protocol exhibits extraordinary advantages in terms of reactivity and enantioselectivity, given the fact that chiral Rh(III) complex at an amount as low as 0.05 mol% can promote the title reaction on the gram scale to afford the desired product, with excellent enantioselectivity (96% ee). Application of the methodology in the efficient synthesis of pyrazolo[3,4-b]pyridine via dehydrogenation is reported.

Graphical abstract: Asymmetric synthesis of 1H-pyrazolo[3,4-b]pyridine analogues catalyzed by chiral-at-metal Rh(iii) complexes

Supplementary files

Article information

Article type
Research Article
Submitted
18 Jun 2024
Accepted
09 Jul 2024
First published
10 Jul 2024

Org. Chem. Front., 2024,11, 5385-5389

Asymmetric synthesis of 1H-pyrazolo[3,4-b]pyridine analogues catalyzed by chiral-at-metal Rh(III) complexes

X. Ji, S. Zhu, Y. Li, Z. Zhao and S. Li, Org. Chem. Front., 2024, 11, 5385 DOI: 10.1039/D4QO01100G

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements