Process for preparing N-(4-cyclohexyl-3-trifluoromethyl-benzyloxy)-acetimidic acid ethyl ester

A process for preparing a compound of the following formula:

• comprising reacting a compound of the formula
• wherein X2 is bromo, chloro, iodo, mesylate, tosylate, triflate or another suitable leaving group, with the compound of formula
• in the presence of a strong base, wherein the starting material of formula IX is synthesized comprising the steps of:
• (a) reacting a compound of the formula
• wherein X is chloro, bromo, or iodo, with a Grignard reagent to form the compound of the formula
• (b) reacting the compound of formula Ill with strong acid to form the compound of formula
• (c) subjecting the compound of formula IV to catalytic hydration to form the compound of formula
• (d) converting the compound of formula V into a compound of the formula
• wherein X1 is bromo, chloro or iodo, by reacting the compound of formula V with 1,3-dibromyl-5,5-diethylhydantoin when X1 in formula VI is bromo, or by reacting the compound of formula V with the appropriate analogous compound when X1 is chloro, fluoro or iodo, in the presence of an acid;
• (e) reacting the compound of formula VI with a Grignard reagent and carbon dioxide to form the compound of formula
• or, alternatively, when carrying out the above reaction of step “e”, adding dimethylformamide to the Grignard reagent to form the corresponding aldehyde of formula
• (f) reducing the compound of formula VII or VIIA to form the compound of formula
• (g) reacting the compound of formula VIII with the appropriate compound of the formula HX2, wherein X2 is defined as it is for formula IX, to form the desired compound of formula IX.