反应详情

A solution containing trimethyloxonium tetrafluoroborate (100 g; 0.68 mol) and methylene chloride (2 liters) is prepared. It is stirred and 5-[2'-chloro-4'-(trifluoromethyl)phenoxy]-2-nitrobenzamide (220 g; 0.61 mol) is then added in portions at ambient temperature. The stirring is continued for 24 hours at ambient temperature. The solution is then washed with a 10% aqueous solution of sodium carbonate (cooled beforehand) and dried over sodium sulphate. The methylene chloride is removed by evaporation to leave a yellow solid of methyl 5-[2'-chloro-4'-(trifluoromethyl)phenoxy]-2-nitrobenzimidate (217 g; yield 95%) melting at 46° C. and having the formula: ##STR20##

1. customis prepared
2. washThe solution is then washed with a 10% aqueous solution of sodium carbonate (cooled beforehand)
3. dry with materialdried over sodium sulphate
4. customThe methylene chloride is removed by evaporation