Versatile method for the synthesis of 4-aminocyclopentenones: dysprosium(III) triflate catalyzed aza-piancatelli rearrangement.
نویسندگان
چکیده
Well-represented in natural products and biologically active molecules, the cyclopentenone scaffold has long been an inspiration for the development of new methodologies. In 1976, Piancatelli and co-workers reported a new method for the synthesis of 4-hydroxycyclopentenone derivatives by an acid-catalyzed rearrangement of suitable 2-furylcarbinols (Scheme 1). The overall transformation is believed to proceed through a cascade sequence that terminates with a 4p electrocyclic ring closure of a pentadienyl cation (D), analogous to the Nazarov cyclization.
منابع مشابه
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عنوان ژورنال:
- Angewandte Chemie
دوره 49 49 شماره
صفحات -
تاریخ انتشار 2010