Studies Of Fluorenyl Derivatives As Organic Function Materials

The dissertation consists of three parts:Syntheses of a series of2-aryl-3,4-diaza-fluorenes and3,4-diazaspirobifluorenes; Concise and efficient syntheses of isotruxene; and Syntheses of fluoreno[2,3-c]furan derivatives.Part one:a series of2-aryl-3,4-diazafluorenes and3,4-diazaspirobifluorenes were reported. The reaction of ninhydrin, arylmethylketone and hydrazine hydrate under reflux afforded2-aryl-3,4-diazafluorenones, which were reduced to2-aryl-3,4-diazafluorenes; On the other hand, the reaction of2-aryl-3,4-diazafluorenones with Grignard reagent of2-bromobiphenyl led to the formation of9-(2-biphenyl)-3,4-diazafluoren-9-ols, which were subsequently converted to2-aryl-3,4-diazaspirobifluorenes by acid-promoted ring closure reaction.Part two:three approaches (a, b, c) to isotruxene were designed and studied, the synthetic route b was found to be efficient with overall yield of34.6%. Initially2,8-dioxo-1,4-diphenylcyclopentadienone was obtained by the reaction of ninhydrin and1,3-diphenylpropan-2-one, then dimethyl9-oxo-1,4-diphenylfluorene-2,3-dicarboxylate was obtained via the Diels-Alder reaction of2,8-dioxo-1,4-diphenylcyclopentadienone and dimethyl but-2-ynedioate, and hydrolysis was employed to afford9-oxo-1,4-diphenylfluoren-2,3-dicarboxylic acid, which was converted into isotruxenone by double Friedel-Crafts acylation in conc. H2SO4with heating. Finally isotruxene was obtained by the Wolf-Kishner reduction of isotruxenone.In addition, we completed the study on synthetic route c, starting with dimethyl9-oxo-1,4-diphenyl-9H-fluorene-2,3-dicarboxylate, isotruxene was synthesized via multiple reactions such as carbonyl protection, ester-reduction, isopropylidene protection of bis(hydroxy-methyl)fluorenone, the Wolf-Kishner-Huang reduction, and deprotection under acidic condition, and finally acid-promoted ring closure in the presence of PPA, the overall yield was30%.Part three:fluoreno[2,3-c]furans were synthesized. First, dimethyl9-oxo-1,4-diphenyl fluoren-2,3-dicarboxylate was reacted with the Grignard reagent of aryl iodide to afford1,4,9-triphenyl-2,3-dibenzoyl-9H-fluoren-9-ol and1,4-diphenyl-9-tolyl-2,3-bis(4-methylbenzoyl)-9H-fluoren-9-ol, which were reacted with anisole or toluene in the presence of BF3-Et2O to afford1,4,9,9-tetraaryl-2,3-diaroxylfluorene; The reaction of1,4,9-triphenyl-2,3-dibenzoyl-9H-fluoren-9-ol or1,4-diphenyl-9-(4-methylphenyl)-2,3-bis(4-methylbenzoyl)-9H-fluoren-9-ol with BF3-Et2O led to the formation of1,4,9-triaryl-2,3-diaroxyl-9H-fluorenes; The reduction of above diaroylfluorenes with LiAlH4afford a series of fluoreno[2,3-c]furans.