反应详情

温度

-5 °C

A mixture of 3.4 ml (43.9 mmol, 10 eq.) of trifluoroacetic acid and 0.33 ml water was cooled to −5° C. At this temperature, 1.88 g (6.59 mmol, 1.5 eq.) of ethyl (1E)-N-[(mesitylsulphonyl)oxy]ethanimidoate [CAS No: 38202-27-6] were added in portions. After 1.5 h, 30 ml of ice-water were added, the mixture was stirred briefly, and the precipitated O-(2-mesitylenesulphonyl)hydroxylamine (MSH) was filtered off by means of a precooled frit and washed with 30 ml of ice-water. The water-moist O-(2-mesitylenesulphonyl)hydroxylamine was dissolved in 12 ml of dichloromethane, dried with magnesium sulphate and filtered, and the filtrate was added dropwise directly to a solution of 1.03 g (4.39 mmol, 1.0 eq.) of 2-[(2,6-difluorobenzyl)oxy]-4-methylpyridine from Example 1A in 2 ml of dichloromethane. The mixture was stirred at RT overnight. Subsequently, diethyl ether was added dropwise, and the precipitate obtained was filtered off, washed with diethyl ether and dried. 1.3 g of the title compound were isolated (59% of theory, 90% purity).

1. filtrationthe precipitated O-(2-mesitylenesulphonyl)hydroxylamine (MSH) was filtered off by means of a precooled frit
2. washwashed with 30 ml of ice-water
3. dissolutionThe water-moist O-(2-mesitylenesulphonyl)hydroxylamine was dissolved in 12 ml of dichloromethane
4. dry with materialdried with magnesium sulphate
5. filtrationfiltered
6. stirringThe mixture was stirred at RT overnight
7. customthe precipitate obtained
8. filtrationwas filtered off
9. washwashed with diethyl ether
10. customdried