Abstract
AbstractThe Gewald reaction has been well-known for more than half a century as an excellent method to provide bioactive 2-aminothiophene heterocycles from the reaction of carbonyl compounds, α-cyanoacetates, and elemental sulfur, in the presence of amines, in stoichiometric amounts. This work describes the use of salts of boric acid as conjugate acid-base pairs in a truly catalytic amount for the cyclocondensation of ketones with active methylenes such as malononitrile, ethyl cyanoacetate, and benzoyl acetonitrile with sulfur to give 2-aminothiophenes via the Gewald reaction. The present protocol is also applied for synthesizing Tinoridine, an anti-peroxidative NSAID, with excellent yield. Additionally, the catalyst has great recyclability and reusability.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.