Patent attributes
2,6-Dimethyl-1-naphthaldehyde having a ratio of the amount of 3,7-dimethyl-1-naphthaldehyde to the total amount of 2,6-dimethyl-1-naphthaldehyde and 3,7-dimethyl-1-naphthaldehyde of 30 mol % or less is particularly useful as optical functional materials, etc. The present invention provides a process for producing such 2,6-dimethyl-1-naphthaldehyde in an industrially advantageous manner. Specifically, in the process for producing 2,6-dimethyl-1-naphthaldehyde through formylation of 2,6-dimethylnaphthalene with carbon monoxide, formylation is performed in the presence of hydrogen fluoride in an amount of 5 to 100 times by mole and boron trifluoride in an amount of 0.5 to 3.5 times by mole, with respect to 2,6-dimethylnaphthalene, and at a reaction temperature of 35 to 70° C.
