Study of the reactivity of ketone enolates with 3-halo-2-amino derivatives of benzo[b]thiophene under photostimulated sRN1 reaction conditions

Reactivity of the 3-halo-2-amino derivatives of benzo6]thiophene 1a-c and 2 with several ketone enolates 3–5 have been studied under photostimulated S_RN1 reaction conditions. The normal substitution product 6 only was obtained in low yields using potassioacetophenone 3 as the enolate ion and 2-(tert-butoxycarbonylamino)-3-chlorobenzob]thiophene ( 1a ) and 2-(tert-butoxycarbonylamino)-3-iodobenzob]thiophene ( 1c ) as substrates. In all reactions the main product was the corresponding dehalogenated substrate 7a-b , thus indicating that reduction of the substrate strongly competes with the desired substitution reaction.