Russian University of Peoples' Friendship, ul. Miklukho-Makaya 6, Moscow, 117198 Russia

摘要

It has been reported earlier that reaction of 1,8-naphtylenediamine I with 1,3-diketones gives rise to either 2-R-2-acyl-2,3-dihydroperimidines or 2-R-per-imidines depending on the reaction conditions [1, 2]. We observed that the reaction proceeded by another route in polyphosphoric acid (PPA contents 86% P2O5; was obtained by [3]). Heating of diamine I with excess of 1,3-diketone IIa-IIc leads to corresponding 2,6,8-trisubstituted 1,3-diazapyrene IIIa-IIIc (Scheme 1).