[C:1]([C:3]1[CH:12]=[CH:11][C:6]2[N:7]=[C:8]([SH:10])[S:9][C:5]=2[CH:4]=1)#[CH:2].[C:13]([O-])([O-])=O.[K+].[K+].CI>CN(C=O)C>[C:1]([C:3]1[CH:12]=[CH:11][C:6]2[N:7]=[C:8]([S:10][CH3:13])[S:9][C:5]=2[CH:4]=1)#[CH:2]To a stirred solution of 6-ethynylbenzo[d]thiazole-2-thiol (4.0 g, 21 mmol) from Step 2 of this Example in 20 mL of DMF at 0° C. were added K2CO3 (7.25 g, 5.25 mmol), and MeI (5 mL). The mixture was stirred at rt for 2 h before it was partitioned between EtOAc and water, the organic layer was washed with brine, dried over Na2SO4, and concentrated under reduced pressure. The residue was purified by silica gel chromatography eluting with 3:1 DCM/hexanes to afford 6-ethynyl-2-(methylthio)benzo[d]thiazole (1.5 g, 35%) as an off-white solid. LCMS (ESI) m/z 206 (M+H)+.
Wird geladen…
