反应详情

温度

0 °C

A mixture of 3.01 g (7.58 mmol) of 2-(4,5-dibromo-3-isopropylthio-2-furanyl)-4,4-dimethyloxazoline and aqueous 4N HCl is warmed at reflux under N2 atmosphere for 0.5 hr. The reaction is cooled to 0° C. and treated with methanol (60 mL), tetrahydrofuran (30 mL), and 4.25 g (177.0 mmol) of anhydrous LiOH. The reaction is stirred at 0° C. for 2 hr and 25° C. for 16 hr, then concentrated in vacuo. The resulting residue is dissolved in H2O and extracted with diethyl ether (2X). The aqueous solution is acidified with aqueous 10% HCl and extracted with ethyl acetate (4X). The combined extracts are washed with aqueous saturated NaCl, dried (Na2SO4), and concentrated in vacuo to afford 1.63 g (2.61 g theo.; 62%) of the carboxylic acid as a beige solid. Recrystallization from diethyl ether/hexane affords an analytical sample; mp 130°-131° C.

1. temperatureis warmed
2. temperatureat reflux under N2 atmosphere for 0.5 hr
3. concentrationconcentrated in vacuo
4. dissolutionThe resulting residue is dissolved in H2O
5. extractionextracted with diethyl ether (2X)
6. extractionextracted with ethyl acetate (4X)
7. washThe combined extracts are washed with aqueous saturated NaCl
8. dry with materialdried (Na2SO4)
9. concentrationconcentrated in vacuo