反应详情

温度

70 °C

) 2-(2H-Benzotriazol-2-yl)-6-chloromethyl-4-methyl-phenol (1.0 g, 3.7 mmol) is partly solved in tetrahydrofurane (20 mL) at 70° C. 2-Ethyl-hexan-1-ol (9.6 g, 73 mmol), potassium tert.butylate (1.0 g, 7.3 mmol), and a catalytic amount of potassium iodide are added subsequently. The orange reaction mixture is stirred at 70° C. for one hour and evaporated to dryness. The residue is dissolved in ethyl acetate and extracted with water. The organic layer is dried over sodium sulphate, filtered and evaporated to dryness. Excess alcohol is removed and recovered by distillation. The crude product is purified by column chromatography (ethyl acetate/heptane 1:12) to yield 1.2 g of 2-(2H-Benzotriazol-2-yl)-6-(2-ethylhexyloxymethyl)-4-methyl-phenol. b.) 2-(2H-benzotriazol-2-yl)-6-chloromethyl-4-methyl-phenol (0.5 g, 1.9 mmol) is suspended in 2-ethylhexan-1-ol (5.0 g, 38 mmol) at 60° C. 1.1 equivalent K2HPO4 is added and the mixture is stirred for 12 hours at 60° C. resulting in 63.3% of 2-(2H-Benzotriazol-2-yl)-6-(2-ethylhexyloxymethyl)-4-methyl-phenol (determined by means of HPLC analysis). c.) 2-(2H-Benzotriazol-2-yl)-6-chloromethyl-4-methylphenol (1.0 g, 3.7 mmol) is suspended in 2-ethylhexan-1-ol (4.0 g, 31 mmol) at 80° C. 1.1 equivalent of the respective base as given in table 1 is added and the mixture is stirred for 15 minutes at 80° C. The turnover and impurity profile is determined by means of HPLC analysis.

1. customevaporated to dryness
2. dissolutionThe residue is dissolved in ethyl acetate
3. extractionextracted with water
4. dry with materialThe organic layer is dried over sodium sulphate
5. filtrationfiltered
6. customevaporated to dryness
7. customExcess alcohol is removed
8. distillationrecovered by distillation
9. customThe crude product is purified by column chromatography (ethyl acetate/heptane 1:12)