e.g. Filippa Pettersson or Cancer Res. 75(6) , 1102-12, (2015) or 10.1002/anie.201600521
A rubrene problem. Reaction of 3, 3, 4, 4-tetrabromo-1, 2-bis (diphenylmethylene) cyclobutane and dichloroacetic acid.
F Toda, M Sasaoka, Y Todo, K Iida, T Hino…
Index: Toda, Fumio; Sasaoka, Michio; Todo, Yozo; Iida, Kunio; Hino, Toru; et al. Bulletin of the Chemical Society of Japan, 1983 , vol. 56, # 11 p. 3314 - 3318
Heating of 3, 3, 4, 4-tetrabromo-1, 2-bis (diphenylmethylene) cyclobutane in dichloroacetic acid afforded bridgehead olefin, 7-bromo-1, 4, 8-triphenyl-2, 3-benzobicyclo [3.3. 0] octa-2, 4, 7-trien-6-one, and spiroketone, 2-bromo-2′, 3-diphenylspiro [1H-indene-1, 1′(4′ H)- naphthalen]-4′-one (13). Mechanism of the reaction was discussed. X-Ray structural study of the spiroketone 13 was also reported.