METHOD FOR PREPARING 2,6-DIFLUOROACETOPHENONES

摘要

Disclosed are methods for preparing compounds of Formula 1 utilizing an intermediate of Formula 4 or an intermediate of Formula 6.;;Also disclosed are compounds of Formula 4.

主权项

1. A method for preparing a compound of Formula 1wherein
R1 is H, F, Cl or Br;comprising (A) contacting a compound of Formula 2with a compound of Formula 3wherein
R2 and R3 are independently CH3, CH2CH3, CH2CH═CH2 or R2 and R3 groups can be taken together as —C(CH3)2— to form a ringand an alkaline earth salt of a strong acid in the presence of a tertiary amine base and an aprotic solvent to form a salt of a compound of Formula 4(B) contacting the salt of the compound of Formula 4 with water and an acid to form the compound of Formula 4 or tautomer thereof, and(C) contacting the compound of Formula 4 with water and heating to a temperature in the range of 85 to 180° C. to give the compound of Formula 1.