1,1'-Thiocarbonyldi-2(1H)-pyridone → 5,6-Dichloro-3-isothiocyanatoisoquinoline

Participants

Reaction Conditions

Reaction Steps

To 6,7-dichloroisoquinolin-3-amine and 5,6-dichloroisoquinolin-3-amine (0.410 g, 1.924 mmol) in dichloromethane (20 mL) was added 1,1′-thiocarbonyldipyridin-2(1H)-one (0.469 g, 2.021 mmol) and the reaction mixture was stirred at 40° C. for 4 hours. The reaction was cooled to room temperature and chromatographed (Biotage: 10-100% ethyl acetate/hexanes) to yield the separated regioisomers, 6,7-dichloro-3-isothiocyanatoisoquinoline (0.2 g, 0.784 mmol, 40.7% yield) and 5,6-dichloro-3-isothiocyanatoisoquinoline (0.23 g, 0.902 mmol, 46.8% yield) as yellow solids. 5,6-dichloro-3-isothiocyanatoisoquinoline: 1H NMR (500 MHz, CDCl3) δ ppm 9.10 (s, 1H), 7.87 (d, J=8.85 Hz, 1H), 7.82 (s, 1H), 7.66 (d, J=8.55 Hz, 1H). MS (LC/MS) R.T.=3.63; [M+H]+=255.0. 6,7-dichloro-3-isothiocyanatoisoquinoline: 1H NMR (500 MHz, CDCl3) δ ppm 9.04 (s, 1H), 8.11 (s, 1H), 7.94 (s, 1H), 7.37 (s, 1H). MS (LC/MS) R.T.=3.42; [M+H]+=255.0.

Provenance & Evidence