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Triarylmethanes (TRAMs) and diarylalkanes (DIAAs) are important intermediates in medicinal, materials chemistry and dye precursors. TRAMs and DIAAs are usually obtained from Friedel–Crafts alkylation reactions. However, because the Friedel–Crafts reaction is catalyzed by Bronsted or Lewis acids, this causes many problems, such as harsh reaction conditions, large amounts of acidic waste liquid after the reaction, etc. All these disadvantages are not good for the environment. In this study, six deep eutectic solvents (DES) were synthesized for this specific reaction. And the DES act as catalyst and solvent. Research showed that DES can be used for catalyzing Friedel–Crafts alkylation of electron-rich arenes with aldehydes under mild reaction conditions. Among the six synthesized DES, a choline chloride–zinc chloride ([ChCl][ZnCl2]2) based DES was shown to be the most efficient catalyst. Using 2.00 equivalents of [ChCl][ZnCl2]2, based on the aldehydes, in the Friedel–Crafts alkylation gave the corresponding TRAMs or DIAAs with the highest yields. The DES was reused directly without any activation process. After five cycles, the yields remained at 89–94%. Finally, a possible mechanism for this reaction is discussed according to the analysis of IR spectrum and further experiments.

Triarylmethanes (TRAMs) and diarylalkanes (DIAAs) are valuable intermediates with wide applications in many fields. TRAMs are usually obtained from the acid-catalysed bisarylation of activated aryl aldehydes. However, the synthesis poses many problems, such as harsh reaction conditions, and the disposal of the excess solvents and/or toxic metal waste. In this study, some functionalized ionic liquids including Bronsted acid ionic liquids (BAILs) and traditional ionic liquids were designed and synthesized. BAILs catalyzed Friedel–Crafts (F–C) alkylation was applied in this specific reaction for the first time. And the BAILs showed bifunctional properties acting as catalyst and solvent. Research shows that BAILs can be used for catalyzing F–C alkylations of electron-rich arenes with aromatic or aliphatic aldehydes successfully under mild reaction conditions. Furthermore, BAILs containing triflic anion has higher activity than other BAILs and traditional ionic liquids. [HSO3-pmim][OTf] gets the highest yields in the presence of 20 mol% of BAILs at 40 °C to give the corresponding TRAMs derivatives. After five cycles, the yields remain about 93–97%. Finally, according to IR spectrum and the experimental validation, the aromatic electrophilic substitution reaction was considered to be the possible catalysis mechanisms.

The present paper dealt with the effect of the avirulent strain RS-1403 of Ralstonia solanacearum on the ecological characteristics of microorganism fatty acids in the rhizosphere of tobacco.The tobacco plants were treated with the avirulent strain RS-1403 in the concentration of 1.0×106 cfu/mL with water as control in the semi experiments.The rhizosphere soil was sampled at different days etc.5d,10d,15d,20d and 25d after treatment.The phospholipid fatty acids(PLFAs) of the soil samples were detected by.GC of Agilent6890N.Pattern,content and structure of the microbial PLFAs in tobacco rhizosphere soil were evaluated and the difference between treatment and water control were compared to analyze the immune disease-resistant mechanism of the strain RS-1403 against tobacco bacterial wilt disease at the microbial community level.The results showed that the microbial PLFAs pattern and content in the tobacco rhizosphere soil were changed under the stress of the avirulent strain RS-1403.The fluctuation of microbial PLFAs could be divided five types,e.g.declining type,unchanging type,50% increasing type,50%—100% increasing type,and 100% increasing type.Among which,the reduction of 10Me16 ∶0 indicative to actinomycetes represented the decreasing type,all of the PLFAs in 100% increasing type indicated to G-bacteria.The statistical analysis showed that the inoculation of RS-1403 could change the microbial community structure in the tobacco rhizosphere soil due to improving the growth of bacteria and fungi and inhibiting the reproduction of actinomycetes.Inoculation of the stain RS-1403 could increase the microbial community diversity in the soil,in which,the enhancement of SHANNON index of community dominance,Simpson index of community abundance and Pielou index of uniformity was revealed.The differentiation of microbial sub-community in the tobacco rhizosphere soil under the stress of the strain RS-1403 was also evaluated with cluster analysis.The results displayed the significant difference existed between RS-1403 treatment and water control.The rhizosphere soil microbe both in treatment and control could be divided into four sub-communities at 2.56 Lance-distance,which were different in the constitutes and characters of PLFAs.The tobacco rhizosphere soils in the RS-1403 threatening treatment and water control could be mainly clustered in to two different groups by using cluster analysis,it was clear that the RS-1403 could alter remarkably microbial community structure in the rhizosphere soil of tobacco.

Triarylmethanes and diarylalkanes are synthesized by the title method under mild reaction conditions in high yields.