AI Article Synopsis
- A new and highly effective vinylogous Mannich reaction has been developed, which combines benzothiazolimines with γ-butenolides, using a quinine-based squaramide as a catalyst.
- This reaction yields chiral benzothiazole amines that have a unique γ,γ-disubstituted butanolide structure, achieving high yields (up to 91%) and excellent enantioselectivities (up to >99% ee) and diastereoselectivities (over >20:1 dr).
- The resulting compounds could pave the way for the creation of new pharmaceutical drugs due to their complex stereochemical framework.
Article Abstract
A highly effective and enantioselective vinylogous Mannich reaction between benzothiazolimines and γ-butenolides catalyzed by a quinine based squaramide has been disclosed. A series of chiral benzothiazole amines containing a γ,γ-disubstituted butanolide scaffold bearing an adjacent chiral stereocenter have been successfully obtained in good to excellent yields (up to 91%) with excellent enantioselectivities (up to >99% ee) and diastereoselectivities (>20 : 1 dr) with broad substrate generality under mild conditions. The new scaffold integrated with both chiral benzothiazolimine and γ-butenolide moieties may provide a possibility for the development of new pharmaceutical entities.
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| http://dx.doi.org/10.1039/d4ob01175a | DOI Listing |
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