反应详情

To a slurry of 14.8 g (0.0863 mol) of 2-amino-4-chlorobenzoic acid and 150 ml of phosphorous oxychloride is added dropwise 10 g (0.086 mol) of tetrahydrothiopyran-4-one. The mixture is stirred at reflux for 3 hours and then concentrated in vacuo. The residue is dissolved in methylene chloride and added slowly to an ice-NH4OH mixture. The mixture is stirred for 1/2 hour and extracted with methylene chloride. The combined extracts are washed with water, dried over Na2SO4, and concentrated in vacuo to yield a dark solid. Trituration with ether furnishes 15 g (64%) of title compound: m.p. 112°-115° C.; IR (KBr) 1605, 1480, and 1415 cm-1 ; NMR (CDCl3) δ8.08-8.02 (m, 2H), 7.58-7.52 (m, 1H), 4.08 (s, 2H), 3.44 (t, 2H), and 3.08 (t, 2H).

1. temperatureat reflux for 3 hours
2. concentrationconcentrated in vacuo
3. dissolutionThe residue is dissolved in methylene chloride
4. additionadded slowly to an ice-NH4OH mixture
5. stirringThe mixture is stirred for 1/2 hour
6. extractionextracted with methylene chloride
7. washThe combined extracts are washed with water
8. dry with materialdried over Na2SO4
9. concentrationconcentrated in vacuo
10. customto yield a dark solid