Patent ID: 7241925
Filing Date: 2007-07-10
Classification: C07C

Abstract:
1. A method for producing a halogen-substituted aromatic aldehyde comprising a step of converting a halogen-substituted aromatic compound represented by the following formula 1: wherein R 1 , R 2 , R 3 and R 4 are the same or different and each represents hydrogen atom or aliphatic hydrocarbon group having 1 to 6 carbon atoms, X is fluorine atom when R 1 , R 2 , R 3 and R 4 are all hydrogen atom, and X is halogen atom selected from the group consisting of fluorine atom, chlorine atom, bromine atom and iodine atom when at least one of R 1 , R 2 , R 3 and R 4 is the aliphatic hydrocarbon group, hydrogen being in the para-position to X, into the halogen-substituted aromatic aldehyde represented by the following formula 2:  wherein X, R by a reaction with carbon monoxide in the presence of hydrogen fluoride and boron trifluoride, wherein said converting is carried out at a reaction temperature of 0° C. or lower.