Retene, methyl isopropyl phenanthrene or 1-methyl-7-isopropyl phenanthrene, C18H18, is a polycyclic aromatic hydrocarbon present in the coal tar fraction, boiling above 360 °C. It occurs naturally in the tars obtained by the distillation of resinous woods.
Plates or scales (from ethanol) or pearly-beige small flakes.
Upon treatment with CrO3 in acetic acid forms RETENEquinone (C18H1. .
Crystallise retene from EtOH. The picrate has m 126o (from EtOH). The 1:1 1,3,5-trinitrobenzene-complex has m 144o (from EtOH). [Beilstein 5 H 683, 5 II 598, 5 III 2199.]
