A Study On Synthesis Of Polychloromethylated Aromatic Compounds And Their Derivatives

The Blanc chloromethylation reaction of arene still plays an important role in many organic reactions_, which has been widely applied in synthesizing many chloromethyl aromatic hydrocarbon monomers that widely used in medicine_, pesticide_, paint_, organic additives_, polymer materials_, etc.At present_, there are many methods to synthesize chloromethylarene. But the yield of traditional chloromethylation reaction is usually very low. In particular_, some problems about low production are still unsolved when we synthesize some polychloromethylated compounds. In this circumstance_, a novel composite catalyst prepared from lewis acid_, organic acid_, and inorganic acid in a certain ration had been applied to synthesize some polychloromethylarenes through the chloromethylation reaction in this paper. Under atomaspheric pressure_, 4_,4^′-bis(chloromethyl)biphenyl_, 1_,5-bis(chloromethyl)naphthalene_, 2_,4_,6-tri(chloromethyl)toluene_, 2_,4_,6-tri(chlorome- thyl)ethylbenzene_, 2_,4_,6-tri(chloromethyl)isopropylbenzene_, 2_,4_,6-tri(chloromethyl)- m-xylene_, 2_,4_,6-tri(chloromethyl)mesitylene were successfully prepared from biphenyl_, naphthalene_, methylbenzene_, ethylbenzene_, cumene_, m-xylene_, mesitylene_, respectively via polychloromethylation by using this novel composite catalyst. The factors that affect the reactions and yields were investigated systematically. It was found that this new synthetic method has many advantages such as easy manipulations_, facile raw materials_, high yields_, mild reaction conditions_, high-quality productions_, which is suitable for industrialized manufacture and has potential application prospects.Furthermore_, the chloromethyl functional groups of arene can be easily converted into many other useful active groups_, such as -CHO_, -COOH_, -CH₂COOH_, -CH₂N(CH₃)_2, -CN_, -CH₂NH_2, -CH₂CN_, -CH₂OCH_3, -CH₂OH_, -CH₂R_, and so on. In order to realize material conversion and improve the performance of productions_, we have tried to synthesize various derivatives of chloromethylarenes through a series of reactions from corresponding chloromethylarenes. The as-synthesized derivatives are as follows: 4_,4^′-bis(methoxymethyl)biphenyl_, 4_,4^′-bis(hydroxymethyl)biphenyl_, 4_,4^′-biphenyldicarbonitrile_, 1_,5-bis(methoxymethyl)naphthalene_, 1_,5-bis(hydroxy- methyl)naphthalene_, 1_,5-naphthalenedicarbonitrile_, 2_,4_,6-tri(methoxymethyl)toluene_, 2_,4_,6-tri(hydroxymethyl)toluene_, 2_,4_,6-tri(methoxymethyl)-m-xylene_, 2_,4_,6-tri(hyd- roxymethyl)-m-xylene_, 2_,4_,6-tri(methoxymethyl)mesitylene_, 2_,4_,6-tri(hydroxymeth- yl)mesitylene_, 2_,4_,6-tri(methoxymethyl)ethylbenzene_, 2_,4_,6-tri(methoxymethyl)isop- ropylbenzene.The structures of the as-synthesized compounds are all confirmed by 1H-NMR_, 13C-NMR_, FT-IR and several other means. All characterization results of these compounds are consistent with the reported literature data and theoritical consequences. Among all compounds_, 2_,4_,6-tri(methoxymethyl)toluene_, 2_,4_,6-tri- (methoxymethyl)isopropylbenzene_, 2_,4_,6-tri(methoxymethyl)ethylbenzene_, 2_,4_,6-tri- (chloromethyl)ethylbenzene_, 2_,4_,6-tri(hydroxylmethyl)-m-xylene_, didn't reported in any other literatures.