M. Barnett, G. Daub, F. Hayes
May 1, 1960
Citations
0
Influential Citations
17
Citations
Journal
Journal of the American Chemical Society
Abstract
Fluorene-2-carboxylic acid was prepared, either by treatment of 2- acetylfluorene with one equivalent of iodine in excess pyridine followed by basic cleavage of the intermediate pyridinium salt, or by direct carboxylation of fluorene with oxalyl chloride. The reaction of fluorene2-carbonyl chloride(I) with the appropriate alpha -aminoketone salt gave 1-(2-fluorenyl)-4-aryl-2-aza- 1.4-butanedtones which were cyclized to the respective oxazoles wtth phosphorus oxychloride. 2-(1- Fluorenyl)-5-phenyl-1,3,4oxadiazole was prepared by cyclization of 1-benzoyl-2(fluorene-2-carbonyl) -hydrazine, obtained by the reaction of I with benzoylhydrazine. The oxazoles and oxadiazole were evaluated as primary liquid scintillation solutes. In addition, 5-(4-biphenylyl) -2-(2- fluorenyl)-oxazole, 2-(2fluorenyl)-5-(1-naphthyl)-oxazole and 2-(2-fluorenyl)-5(2- naphthyl) -oxazole were screened as potential secondary solutes. The compounds exhibited excellent scintillation characteristics. (auth)