From 1, 4-diphenylbutadiene, 1, 4-diphenylfluorenone (11) was thus obtained. Dicyclohexenyl gave 1, 2, 3, 4-bis-(tetramethylene)-fluorenone (111). Comparison of the ultraviolet spectrum of I1 and I11 with that of fluorenone7J shows that in both cases a bathochromic shift has taken place (fluorenone, 378; 11, 412; 111, 394 mp). While this shift was to be expected in the case of 11, one may have to attribute it for 111 to the same ...
