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Herein, we present an efficient strategy for the synthesis of spiro(indenyl)cyclohexadienones through radical‐promoted reaction of 2‐alkynyl biaryls with sodium sulfinates under electrochemical conditions. The reaction involves sulfonylation and dearomative ipso‐cyclisation in a domino fashion. This approach features the use of readily accessible precursors, wide functional group tolerance and external oxidant‐free reaction conditions. The practicality of the method was also illustrated by scale‐up reaction and further diversification of the product. [ABSTRACT FROM AUTHOR]

Iodine-mediated oxidative annulations of N -benzyl-propiolamides are disclosed for the first time, providing either azaspiro[5.5]undecatrienones via dearomative ipso -annulation or benzo[ c ]azepinones through ortho -annulation. The selective construction of the aforementioned products is based on the ceric ammonium nitrate (CAN)-promoted divergent reactivity of the propiolamide, directed by the substituents on the phenyl ring of the N -benzyl group. [ABSTRACT FROM AUTHOR]

Herein, we present the electrochemical synthesis of selenylated azaspiro[4.5]decadienones through domino selenylation/ ipso -annulation of N -benzylacrylamides with diselenides. The method showed a wide substrate scope under mild and external oxidant-free reaction conditions, involving the construction of C-Se and C-C bonds. Gram-scale synthesis and further functional group conversion of the product are also demonstrated.

A variety of acrylamides holding an unactivated N -benzyl group underwent dearomative ipso -cyclization induced by sulfur-centered radicals (SCN/ SCF 3 / SO 2 Ar) in the presence of ceric ammonium nitrate (CAN) as the oxidant to furnish azaspirocycles in good yields. This is the first report on ipso -dearomatization of N -benzyl acrylamides that proceeds without a substituent at the para -position of the aromatic ring. The developed conditions are also found to be suitable for substrates holding substituents such as F, NO 2 , OMe, OH, and OAc at the para -position. The reaction features water as the source of oxygen, is compatible with a variety of functional groups, and proceeds in a short time.