Online article for Non-subscribers

Pay per view

Heterocycles has a pay-per-view service for Non-subscribers.
You will be able to directly purchase the full text article through PayPal.
Your purchased Paper can be downloaded after the payment is completed.
An e-mail will be sent the URL to download the paper.
If you have any questions, please contact: purchase@heterocycles.com

Price: ¥ 4,400 (Yen only)
Period: This Article can be accessed for 7 days.

Paper | Regular issue | Vol 98, No. 10, 2019, pp.1408-1422
Published online, 1st November, 2019
DOI: 10.3987/COM-19-14158
Fast, Solvent-Free, and Highly Efficient Synthesis of Pyrazolo[3,4-b]Pyridines Using Microwave Irradiation and Khso4 as A Reusable Green Catalyst

Jinjing Qin, Zhenhua Li,* Xiaomeng Sun, Yi Jin, and Weike Su

*Collaborative Innovation Centre of Yangtze River Delta Region Green Pharmaceuticals, College of Pharmaceutical Sciences, Zhejiang University of Technology, 18#, Chaowang Rd., Hangzhou, Zhejiang 310014, China

Abstract

A simple, ecofriendly, and effective method was described for forming pyrazolo[3,4-b]pyridines from 5-aminopyrazoles and 3-formylchromones, in good to excellent yields, under microwave irradiation in solvent-free conditions using KHSO4 as a reusable catalyst. Some noteworthy features of this method were its cleanliness, short reaction time, easy work-up, and broad substrate tolerance. The catalyst was reused several times without losing activity.