LOCATION OF DOUBLE BONDS IN FLUORANTHENE PERYLENE AND 1,1'-DINAPHTHYL BY NMR

1-Methyl-, 3-methyl-, 8-methyl-, 1,3-dimethyl-, 7, 10-methyl-, and 8,9-dimethylfluoranthene were synthesized and their NMR spectra recorded. The results show double bonds in the positions: 2,3-, and 4,5- which are equivalent to the fixed double bond in 9,10-position in phenanthrene. There is a high degree of double bond character in 8,9-position. The electronic spectra of fluoranthene,2,3-benzo-fluoranthene, naphtho[2′:3′, 2:3]fluoranthene are compared. This shows that the fluoranthene type of spectrum changes gradually into the phene type spectrum. There are no fixed double bonds in 3,10-dimethylperylene and 4,4′-dimethyl-1,1′-dinaphthyl. © 1969.