The invention discloses a preparation method of a symmetric
phosphine oxide type TADF organic photoelectric material, and belongs to the field of organic functional materials. 2, 2 '-dinitro-
biphenyl is subjected to stannous
chloride reduction, amido
acylation,
electricity-rich aromatic ring bromination reaction and acid deacylation of a
protecting group to form free amido, the amido is converted into 5, 5'-dibromo-2, 2 '-diiodo-
biphenyl through a diazonium salt process, then the 5, 5'-dibromo-2, 2 '-diiodo-
biphenyl is converted into 5, 5'-dibromo-2, 2 '-diiodo-biphenyl, and the 5, 5'-dibromo-2, 2 '-diiodo-biphenyl is converted into 5, 5 The preparation method comprises the following steps: carrying out
lithium-
iodine exchange on 2, 2 '-diiodo-biphenyl, carrying out
nucleophilic substitution reaction on the 2, 2'-diiodo-biphenyl and
dichlorophenylphosphine to generate
phenylphosphine heterobenzoindole, oxidizing the
phenylphosphine heterobenzoindole to form
phenylphosphine oxide heterobenzoindole, and carrying out
coupling reaction on brominated
aromatic hydrocarbon and heteroaromatic
hydrocarbon under the
catalysis of
copper to synthesize the small organic molecule
luminescent material with fluorescent
reactive oxygen species. The 2, 8-diphenothiazinyl-5-phenyl benzoxphosphine heteroindole synthesized by the method has the potential of becoming an organic micromolecule electroluminescent material and being used as a
photosensitizer for organic photoreaction, and fits the development trend of multifunctional application of organic micromolecule materials.