反应详情

To a cooled 5° C., stirred solution of (R)-1-(6-chloro-pyridin-3-yl)-ethane-1,2-diol (17.8 grams) in anhydrous pyridine (100 mL) was added p-toluenesulfonyl chloride (19.5 grams) in one portion. After 20 minutes, the cooling bath was removed and stirring was continued an additional 12 hours. The reaction solution was concentrated in vacuo, azeotroped with toluene (2 times), diluted ethyl acetate, washed with half-saturated aqueous brine, saturated aqueous brine, dried over sodium sulfate and concentrated in vacuo. The resulting solids were recrystallized from ethyl acetate/hexanes to afford the title compound as colorless crystals, 23.3 grams 1H NMR (400 MHz, CDCl3)=8.29 (s, 1H); 7.72 (d, 2H); 7.64 (d, 1H); 7.32 (d, 2H); 7.28 (d, 1H); 5.00 (dd, 1H); 4.09 (AB pattern, 2H); 2.44 (s, 3H).

1. customthe cooling bath was removed
2. waitwas continued an additional 12 hours
3. concentrationThe reaction solution was concentrated in vacuo
4. customazeotroped with toluene (2 times), diluted ethyl acetate
5. washwashed with half-saturated aqueous brine, saturated aqueous brine
6. dry with materialdried over sodium sulfate
7. concentrationconcentrated in vacuo
8. customThe resulting solids were recrystallized from ethyl acetate/hexanes