As part of a continuing project directed toward the total synthesis of several terpenes, we required large amounts of the well-known annelating reagent ethyl 3-oxo-4-pentenoate (1, Nazarov's reagent).'The synthesis and use of this compound as an annelating agent have been reported in the literature many time^.^-^ We required a facile, short, and efficient synthesis of 1, readily providing large quantities.
