CN(C)C(=O)[S:4][C:5]1[CH:16]=[CH:15][C:8]2[C:9]([CH3:14])=[CH:10][C:11](=[O:13])[O:12][C:7]=2[CH:6]=1.C[O-].[Na+].C(OCC)(=O)C.C1(C)C=CC=CC=1.O=P12OP3(OP(OP(O3)(O1)=O)(=O)O2)=O>CO>[SH:4][C:5]1[CH:16]=[CH:15][C:8]2[C:9]([CH3:14])=[CH:10][C:11](=[O:13])[O:12][C:7]=2[CH:6]=126.3 g (0.1 mol) of S-(4-methyl-2-oxo-2H-1-benzopyran-7-yl) dimethylthiocarbamate are suspended in 300 ml of methanol under a nitrogen atmosphere. 0.2 mol of sodium methylate (8% solution of Na (w/v) in methanol) is added at room temperature and the mixture is heated at 45° C. for 4 hours. The disappearance of the starting material is monitored by thin layer chromatography using an ethyl acetate/toluene mixture (1/4 v/v) as the eluent. After cooling, the reaction medium is hydrolyzed on an ice/concentrated hydrochloric acid mixture and, after stirring for 30 minutes, the precipitate obtained is filtered off and then washed with water. After drying over P2O5, 19.2 g (yield≈100%) of the expected product are obtained.
Loading…