New formylating agents - Preparative procedures and mechanistic investigations

The reactivity of new formylating agents related to formamide has been inve stigated both experimentally and theoretically. The reaction in 1,2-dichlor oethane between tris(diformylamino) methane (2) and several arenes, catalyz ed by AlCl3 or BCl3, was shown to proceed in good yields to afford the corr esponding para-substituted aldehydes. The nature of the active electrophili c species was also investigated theoretically, Thus, the relative stability of the O- and N-protonated forms, as well as those of AlCl3 adducts, of se veral formylating agents - diformamide, triformamide, N,N,N ' ,N ' -tetrafo rmylhydrazine, and tris (diformylamino) methane-were determined in the gas phase and in water or DCE by means of DFT calculations at the B3LYP/6-311+G(d,p) level, the solvents being modeled-with the IPCM method. The amide ox ygen atom in all cases appeared to be the most basic site, both in the Bron sted and Lewis sense, constituting a first step towards the understanding o f the mechanism of this reaction.