[CH3:1][O:2][CH2:3][C:4]1[S:8][C:7]2=[N:9][C:10]([C:12]([F:15])([F:14])[F:13])=[CH:11][N:6]2[N:5]=1.[CH2:16]=[O:17].Cl.O>S1(CCCC1)(=O)=O>[CH3:1][O:2][CH2:3][C:4]1[S:8][C:7]2=[N:9][C:10]([C:12]([F:15])([F:13])[F:14])=[C:11]([CH2:16][OH:17])[N:6]2[N:5]=12-(methoxymethyl)-6-(trifluoromethyl)imidazo[2,1-b][1,3,4]thiadiazole a2 (10 g, 42.16 mmol, 1 eq), formaldehyde (16 g, 421.6 mmol, 10 eq) and hydrochloric acid (37%, 8.2 ml, 2 eq) are diluted in sulfolane (250 ml). The reaction mixture is heated at 110° C. overnight. Water (500 ml) is added and the mixture is heated at 50° C. for 2 h. The solvent is then removed under reduced pressure. The residue is purified by chromatography over silicagel (gradient; eluent: CH2Cl2/MeOH/NH4OH from 100/0/0 to 99/1/0.1) to afford 6.5 g of [2-(methoxymethyl)-6-(trifluoromethyl)imidazo[2,1-b][1,3,4]thiadiazol-5-yl]methanol a3 as a yellow solid.
Loading…