Phosgene → 6-Fluoro-5-isocyanato-3-propargyl-2-benzothiazolone
Reaction equation
[NH2:1][C:2]1[C:3]([F:15])=[CH:4][C:5]2[S:9][C:8](=[O:10])[N:7]([CH2:11][C:12]#[CH:13])[C:6]=2[CH:14]=1.[C:16](Cl)(Cl)=[O:17]>C(OCC)(=O)C>[F:15][C:3]1[C:2]([N:1]=[C:16]=[O:17])=[CH:14][C:6]2[N:7]([CH2:11][C:12]#[CH:13])[C:8](=[O:10])[S:9][C:5]=2[CH:4]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 50 °C
Procedure
A solution of 22.5 g of 5-amino-6-fluoro-3-(2-propynyl)-2-benzothiazolinone in 350 ml of ethyl acetate is added dropwise at 30° C. during 2 hours while stirring to a solution of 60.0 g of phosgene in 300 ml of ethyl acetate. The resulting suspension is stirred at 50° C. for 2 hours and subsequently heated slowly to the boiling point. The clear solution is then evaporated to dryness and there is thus obtained as the residue 6-fluoro-5-isocyanato-3-(2-propynyl)-2-benzothiazolinone, yellow crystals. This product serves, inter alia, as the starting material in the manufacture of 3-[6-fluoro-2-oxo-3-(2-propynyl)-5-benzothiazolinyl]-6-trifluoromethyl-2,4-(1H,3H)-pyrimidinedione (see Example 1).