Synthesis of Trifluoromethylselenolated Spiro[5.5]trienones/Spiro[4.5]trienones via Electrophilic Trifluoromethylselenolation Cyclization and Dearomatization

An expedient strategy for the construction of trifluoromethylselenolated spiro[5.5]trienones/spiro[4.5]trienones through a cascade electrophilic trifluoromethylselenolation cyclization and dearomatization has been developed. This sequential process was induced by N ‐trifluoromethylselenophthalimide (Phth‐SeCF 3 ), which was an efficient electrophilic trifluoromethylselenolation reagent. This approach has the feature of mild conditions, broad substrate scope, and high functional group tolerance.