The Investigation Of Green Synthetic Methods Of Bis(indoly) Methanes

Indoles are a class of heterocycle with important physiological function and pharmacological activity through the life process.The development of new efficient selectives has attracted sustained attention in organic synthesis due to their important biological activites and key role as versatile building bocks in the synthesis of natural products and therapeutic agents.Bis(indolyl)methanes and their derivatives are found in bioactive metabolites of terrestrial and marine origin.They are efficient anti-cancer drugs.With continuously investigation of bis(indolyl)methanes,several synthetic methods have been reported.Consequently,instruction of efficient and mild methods for the preparation of bis(indolyl)methanes using less expensive,relatively non-toxic, easy handling and environmentally friendly methods is still in demand.In this paper, on the bisis of synthetic methods of bis(indolyl)methanes's review,three new catalytic systems with Oxone-CH₃OH,Bu₄NHSO₄-H₂O,Bu₄NHSO₅-H₂O were investigatied for the preparation of bis(indolyl)methanes.The paper mainly consists of three parts:The first part:Literature review.A brief review of the existence and function of some important indole compounds,besides,the research progress of bis(indolyl)methanes of synthesis.The second part:Synthesis of bis(indolyl)alkanes catalyzed by Oxone.First, with Oxone(2KHSO₅·KHSO₄·K₂SO₄) as catalyst,1,2-dimethyl-indole and p-methoxybenzaldehyde were chosen as substrates to investigate the optimum solvent at room tempeture.The methol was identified as best solvent.Then the optimum reactions of the amount of catalyst and reaction time were investigated.14 renactions of different indoles with aromatic aldehydes were carried out according to the reaction conditions.The results showed that(1.1 mol%) was found to be an effectivecatalyst for the condensation reactions in good to excellent yields within 10-30min at room temperature.Among the products,6 products haven't been reported in the literature.Followed,(1) the structure of 3,3-Bis(1,2-methyl-indolyl) -p-methoxyphenylmethane(1b) was further established by the X-ray diffraction study; (2)The possible mechanism is sketched;(3) the reuse of oxone was studied.We found that even after five runs,oxone still has relatively high activity.So we described an mild and efficient and environmentally friendly procedure for the preapation of bis(indolyl)methanes with cost efficient and recycled oxone.The third part:Synthesis of bis(indolyl)methanes assisted by two phase transfer catalysts.First,at room tempeture with water as solvent and Bu₄NHSO₄,Bu₄NHSO₅ was supplied as catalysts separately,1,2-dimethyl-indole and p-methoxybenzaldehyde were chosen as substrates to investigate the optimum reaction conditions of the amount of catalyst and reaction time.33 renactions of different indoles with aldehydes were carried out according to the optimum reaction conditions. Experimental results showed that Bu₄NHSO₅ in the aqueous phase can efficiently catalyzed the electrophilic substitution reaction of different indoles with aromatic aldehydes.Then for Bu₄NHSO₄,chemical equivalent of catalyst can assist reactions of indole and aromatic aldehydes.As water was chosen as a green solvent and replaced the traditional organic solvents,and also quaternary ammonium salts were used as catalysts,so the two methods are green and efficient synthetic method.Finally,we make a conclusion to the article and look forward to the development of the kinds of the compounds were synthesized.Some spectra are listed.