| Studies on synthesis of benzene derivatives are very important in the synthetic chemistry and practical application. The key issue is the relatively poor selectivity. To the present there is no report for preparation hexasubstituted benzenes which have the same substituent in the 3 and 6 positions, and the same substituent in 4 and 5 positions. The new method on systhesis of these new kind of compounds is reported first in this dissertation. In the dissertation, 3,6-diiodo-phthalic acid dimethyl esters are prepared by bis ipso iododesilylation of 3,6-bis-trimethylsilanyl-phthalic acid dimethyl esters. Then 3,6-diiodo-phthalic acid dimethyl esters occur substitution reaction with electrophiles and we can get the target compounds. When the electrophile is alkyl iodide, lithiation on 3,6-diiodo-phthalic acid dimethyl ester and then quenching with excess electrophile give the 3,6-dialkyl-phthalic acid dimethyl ester. When the electrophile is thienyl iodide and aryl iodide, we can't prepare the target compounds using lithiation. We prepare 3,6-dithienyl- phthalic acid dimethyl ester using Negishi coupling and 3,6-diaryl- phthalic acid dimethyl ester using Suzuki coupling. The three methods all get hexasubstituted benzenes which have the same substituent in the 3 and 6 positions, and the same substituent in 4 and 5 positions with excellent selectivity in high yields.Quinoline derivatives have important areas of applications in pharmaceutical, molecular biology and dyestuff insudtry, so the systhesis of quinoline derivatives have important significance both in methodology and practical application. In this dissertation, we carry out the coupling reaction of azazirconacyclopentadienes, which are conveniently prepared from zirconocene with one internal alkyne and one nitrile,with substituted diiodobenzenes at the first time,and get a series of quinoline derivatives. We also study the effects of azazirconacyclopentadiene substituents and diiodobenzene substituents on the coupling reaction.
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