Synthesis Of Aza-crown Ether And Mono-quinolinyl 9, 9’-Spirobifluorene Derivatives

The present paper is composed of two parts: Synthesis of the Aza-Crown ether compounds and Mono-quinoline substitutued 9, 9’-Spirobifluorene derivatives.In part one, two type of Aza-crown ethers are synthesized, one is the N-pivot lariat crown ether, another is calix[4]crown ether Schiff base. Two synthetic approaches to N-lariat benzo-15-Crown-5 are described and compared. The empirical datum showed that, Mannich reaction is more effective and convenient for the synthesis of N-pivot lariat monoazabenzo-15-Crown-5 than Hofmann alkylation when the phenoxy group is introduced to the nitrogen atom of crown ether. The reaction could be completed in one-pot synthesis with better yield and convenient work-up process. Many attempts have been made to prepare and purify the starting material monoazabenzo-15-Crown-5, it was found that recrystallization of crude product in acetone allowed to obtain product in better yield. Futhermore, we explained the synthetic mechanism of calix[4]arene derivatives. In the process of synthesizing the calix[4]arene compounds, the experimental conditions such as solvent, density of the alkali, reaction temperature etc., have to be strictly controlled to ensure the final product completed in three steps.In part two, two synthetic approaches for synthesis of several 9,9’-spirobifluorene derivatives are reported for the first time. Firstly, 9,9’-spirobifluorene is obtained by Grignard reaction of 2-bromobiphenyl and 9-fluorenone, followed by cyclization reaction under acidic condition. The further acetylation of 9,9’-spirobifluorene led to the formation of 2-acetyl 9,9’-spirobifluorene, which reacts with 2-amino-benzophenones to form mono-quinolinyl 9,9’-spirobifluorene. Another approach started with fluorene, mono-quinolinyl 9,9’-Spirobifluorenes are completed by adapting reactions such as Friedel-Crafts acylation, oxidation, Grignard reaction and cyclization reaction. The reaction mechanisms are also discussed for every step. In synthesis of 2-quinolinyl-fluorene-9-ones, Friedlander reaction is employed to form quinolinyl rings rather than oxidation first. Finally Grignard reaction is also discussed in detail for key intermediates of the 9, 9’-Spirobifluorenes. The UV-Vis and fluorescence spectra of the final 9, 9’-Spirobifluorene quinoline derivatives and their key intermediates are studied and discussed to find the effects of different substitutions on quinolinyl rings.