Patent ID: 6608217
Filing Date: 2003-08-19
Classification: C07C,C07D

Abstract:
A process for producing a 2,2-bis(fluoromethyl)-6-(perfluoroalkyl)-2H-1-benzopyran-4-carboxylic acid represented by the general formula [1], the process comprising the steps of:(a) reacting a 2,2-bis(fluoromethyl)-6-(perfluoroalkyl)-2 H-1-benzopyran-4-one, represented by the general formula [2], with a perfluoroalkanesulfonic acid anhydride, represented by the general formula [3], in the presence of a base, thereby obtaining a perfluoroalkanesulfonic 2,2-bis(fluoromethyl)-6-(perfluoroalkyl)-2 H-1-benzopyran-4-yl ester represented by the general formula [4]; and (b) reacting the benzopyranyl ester with carbon monoxide in the presence of a palladium complex compound and a base, thereby obtaining the carboxylic acid, where R1 is a perfluoroalkyl group that is represented by CnF2n+1 where n is an integer of 1-10 and that optionally has a branch in a carbon structure of the perfluoroalkyl group; each of R2 and R3 is independently a lower perfluoroalkyl group that is represented by CnF2n+1 where n is an integer of 1-10 and that optionally has a branch in a carbon structure of the lower perfluoroalkyl group; and R4 is identical with the R2 or R3.