“…Simple 1H-benzo[de]cinnolines have been prepared by Lacy and Smith, Scheme 1(a) 5 and 1(b), 6 and by Aksenov, Aksenova et al, 7 Scheme 1(c). Using the methods represented in Scheme 1(a), a series of 1H-benzo[de]cinnolines have been prepared (Figure 2) by Mezheritskii et al, [8][9][10][11][12][13] A totally different method has been reported by Chenoweth et al, 8 (cited in 9 ). A very complex and beautiful reaction, starting from 3,6-dimethyl-1,2,4,5-tetrazine and o-benzyne, allows to prepare compound 20, 4-methyl-6-phenyl-6H-dibenzo[de,g]cinnolin 10 They have prepared a large set of compounds, 20-32, and some dimethyl derivatives starting from 4,5-dimethyl-o-benzyne (Scheme 2).…”