Abstract
The reactivity of the Hauser-Kraus (H-K) donor, 3-sulfonylphthalide, with various activated imines under basic conditions is demonstrated. The reaction of 3-sulfonylphthalide with Boc-protected aldimine provides a rapid access to 1,2-imine adducts and alkylidenephthalides depending upon the stoichiometry of the base. The alkylidenephthalides could be transformed to ketophthalides, a new class of phthalides, on acid hydrolysis, which upon reductive cyclization using Zn/AcOH afforded the natural product homalicine. On the contrary, the Boc-protected isatinimines undergo an efficient H-K annulation to provide spiro-isoquinolinone-oxindoles in excellent yields. However, the corresponding conjugated ketimines afforded Michael adducts, which were converted to the corresponding alkylidenephthalides under TBAF conditions.
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.