Article révisé par les pairs
Résumé : We have synthesized 1:2, 3:4, 6:7‐tribenzfluorene (IV) by reduction of the corresponding fluorenone prepared by condensation of phthalaldehyde with 4:5, 6:7‐dibenzindanone. Potash fusion of 1:2, 3:4, 6:7‐tribenzfluorenone gave a mixture of the following two acids which have been separated and characterized: 9‐(β‐naphthyl) 10‐phenanthroic acid (V) 2‐(9′‐phenanthryl) 3‐naphthoic acid (VI). The former (V) afforded, by cyclisation, 1:2, 3:4, 7:8‐tribenzfluorenone from which, by reduction, 1:2, 3:4, 7:8‐tribenzfluorene (IX) was obtained. The second acid (VI) gave back 1:2, 3:4, 6:7‐tribenzfluorenone on cyclisation. Copyright © 1951 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim