Desymmetrization of Oxabenzonorbornadienes through Brønsted Acid‐Catalyzed Enantioselective (3+2) Cycloaddition with Hydrazones
نویسندگان
چکیده
This work presents the desymmetrization of oxabenzonorbornadienes through (3+2) cycloaddition reaction with hydrazones using a chiral Brønsted acid such as BINOL-derived phosphoramide. catalyst appears most effective mediator for activation hydrazone via hydrazonium cation that reacts in fashion oxabenzonorbornadiene olefinic counterpart. Under optimized conditions, provided selectively exo products satisfactory yields and moderate stereoselectivities. The scope was explored displaying 21 examples these highly functionalized tetrahydroepoxybenzoindazole compounds. A mechanism is proposed to explain outcome reaction.
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ژورنال
عنوان ژورنال: Asian Journal of Organic Chemistry
سال: 2023
ISSN: ['2193-5815', '2193-5807']
DOI: https://doi.org/10.1002/ajoc.202300163