Synthetic development for c-h direct acylation of 1-substituted phthalazines

An efficient and simple method for the regiospecific acylation of 1–substituted phthalazines is described in the presence of tert–butyl peroxybenzoate (TBPB) as an oxidant and AlCl3 as an additive in dichloroethane (DCE) at 110 oC. The reaction involves a coupling reaction between 1–substituted phthalazines with aldehydes or alcohols as an acylating agent through an oxidative cross–dehydrogenative coupling (CDC). This strategy provides an alternative method for the acylation of electron–deficient heteroarenes. To illustrate the applicability of the acylated products, the new route for the synthesis of other functional groups for this class of compound was presented by using a simple chemical reaction that allowed further investigation of their potential biological activities.