2-Methyl-5,6-diphenylanthrapyrazole

Article abstract of DOI:10.1107/S0567740881008327

C28H20N2, M_r=384.5, is triclinic, with space group P1/ and Z=4, a=12.572(3), b=14.832(3), c=12.122(2) Angstroem, α=111.64(1), β=92.56(2), γ=88.64(2) deg, V=2098.7(7) Angstroem³.The density, calculated from the unit-cell volume and contents, is 1.216 Mg m^-3.The structural formula is: .The structure was solved by direct methods (MULTAN) and refined by full-matrix least-squares procedures to a final crystallographic residual of 0.054 for 4005 observed reflections (Cu Kα data).This study establishes that the major product of polyphosphoric acid cyclodehydration of 2-<3-methyl-5-(2-naphthyl)-1-pyrazolyl>-2-phenylacetophenone is 2-methyl-5,6-diphenylanthra<2,1-b>pyrazole.It is concluded that the synthesis of a diazasteroid, a possible product of this reaction, is sterically inhibited.