Research On The Synthesis Of Coenzyme Q₁₀

In this thesis, several routes for synthesis of CoQ₁₀ are tried and discussed, which are generally based on three kinds of strategy.The first synthetic route is based on the wittig reaction, which is aimed of constructing the first C=C double bond of CoQ₁₀. On various conditions, the reaction between Wittig reagent and solanesyl acetone is checked. No desired product is found. It may be due to the steric hindrance of solanesyl acetone, which drastically decreases the reactive activity. Instead of solanesyl acetone, the simpler acetone is checked. The predictable preproduct of CoQ₁ is abtained in the isolated yield of 12.8%.The second route is based on the cross-coupling reaction between Grignard reagent of allylic halide and solanesyl bromide. The synthetic route of the original literature is optimized and the normal coupling product is obtained with isolated yield of 61.5%, instead of the isocoupling product, which was reported.The third one is based on the Biellmann-Ducep coupling reaction, which is almost a versatile method for the formation of 1,5-diene. The key intermidate compounds of CoQ₁₀, 6-(3-methyl-4-chloro-2-butenyl)-2,3,4,5-tetramethoxytoluene and 6-(3-methyl-4-bromo-2-butenyl)-2,3,4,5-tetramethoxytoluene are successfully prepared. CoQ₁₀ is synthesized by Biellmann-Ducep coupling of the later and solanesylsulfone, and then desulfonylation and oxidation. The total yield of above three steps is 19.5%.