RU98114153A - METHOD FOR PRODUCING DIARYLMETHANE OR ITS DERIVATIVES - Google Patents

Claims (13)

1. A method of producing diarylmethane or its derivatives, comprising reacting dimethoxymethane and / or bis (methoxymethyl) ether and an aromatic compound at a reaction temperature in the range of 80 - 400 ° C in the presence of an acid catalyst. 2. The method of claim 1, wherein said diarylmethane and its derivatives are represented by the following general formula I:

where m is an integer 0 to 3, n is 1 or 2, and R is independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or a hydroxyl group.  3. The method of claim 1, wherein said aromatic compound is benzene.  4. The method of claim 1, wherein said aromatic compound is toluene.  5. The method according to any one of paragraphs. 1-4, in which the specified acid catalyst is a solid acid catalyst.  6. A method for producing diarylmethane or its derivatives, comprising the following steps (1) to (4): (1) reacting an alcohol with formaldehyde in the presence of an acid catalyst to produce acetal; (2) the interaction of acetal and aromatic compounds in the presence of an acid catalyst to obtain a reaction mixture containing diarylmethane or its derivatives and alcohol; (3) separating and recovering diarylmethane or its derivatives and alcohol, respectively, from said reaction mixture containing diarylmethane or its derivatives and alcohol; and (4) recycling at least a portion of said reduced alcohol to the preceding acetal preparation step (1).  7. The method of claim 6, wherein the aqueous formaldehyde solution is used as said formaldehyde in step (1), and the reaction mixture in step (3) is extracted with water to separate it into an oil phase and an aqueous phase, then diarylmethane or its derivative is reduced from said oil phase, alcohol is reduced from said aqueous phase, and at least a portion of said alcohol is recycled to said step (1).  8. The method according to p. 6, in which the specified separation and recovery in stage (3) is performed by distillation.  9. The method according to any one of paragraphs. 6-8, in which the indicated alcohol in stage (1) is methanol, and the indicated acetal is dimethoxymethane.  10. The method according to any one of paragraphs. 6-8, wherein said aromatic compound in step (2) is benzene and / or toluene.  11. The method according to any one of paragraphs. 6-8, in which the specified aromatic compound of stage (2) is phenol and / or cresol.  12. The method according to any one of paragraphs. 6-8, wherein said acid catalyst is a solid acid catalyst.  13. The method of claim 6, wherein said reaction of the alcohol with formaldehyde in step (1) is performed by reactive distillation.