STERICALLY HINDERED MONO- AND BIS(2,5-DIARYLOXAZOLES) CONTAINING BIPHENYL SYSTEMS

Article abstract of DOI:10.1007/BF00504197

The condensation of hydrochloric salts of ω-aminomethyl aryl ketones with diphenic anhydride or with the diacid chloride of diphenic acid and subsequent cyclodehydration of the condensation products formed give sterically hindered mono- and bis(2,5-diaryloxazoles) containing the biphenyl system.The spectroluminiscent properties of these compounds were studied.Comparison of the absorption spectra of 2,2'-di(5-phenyloxazolyl-2)biphenyl and 2,5-diphenyloxazole indicates the complete lack of conjugation between the diphenyloxazole fragments, their independent behavior,and their retention of the spatial configuration of 2,5-diphenyloxazole. 2,2'-Di(5-phenyloxazolyl-2)biphenyl has a large Stokes shift.Steric hindrance is also found in 2-carboxy-2'-(5-phenyloxazolyl-2)biphenyl molecules.