[C:1](=[S:3])=S.[NH2:4][C:5]1[CH:6]=[C:7]([CH:11]=[CH:12][CH:13]=1)[C:8]([OH:10])=[O:9].C(N(CC)CC)C.II.Cl.S([O-])([O-])=O.[Na+].[Na+]>C(OCC)(=O)C.O1CCCC1.O>[N:4]([C:5]1[CH:6]=[C:7]([CH:11]=[CH:12][CH:13]=1)[C:8]([OH:10])=[O:9])=[C:1]=[S:3]Carbon disulfide (0.26 mL, 4.4 mmol) was added to a mixture comprising 3-aminobenzoic acid (0.20 g, 1.5 mmol), tetrahydrofuran (1.0 mL), water (1.0 mL) and triethylamine (0.51 mL, 3.6 mmol), followed by stirring at room temperature for 24 hours. To the obtained reaction mixture, a tetrahydrofuran (1.0 mL) solution of iodine (0.41 g, 1.6 mmol) was dropwise added over a period of 5 minutes at 0° C., followed by stirring at 0° C. for further two hours. Thereafter, 1M hydrochloric acid (1.5 mL) and sodium sulfite (38 mg, 0.30 mmol) were added and mixed. Then, ethyl acetate (6 mL) was added, and the organic layer was separated and concentrated under reduced pressure to dryness. To the residue, ethyl acetate (4 mL) and water (2 mL) were added, and the organic layer was concentrated under reduced pressure to dryness to obtain 3-isothiocyanatobenzoic acid as a cream-colored solid (0.25 g, yield: 96%, HPLC purity: 95%, HPLC retention time: 3.6 min). LC-MS ES-178 (retention time: 4.0 min, condition 1).
読み込み中…
