反应详情

To a solution of 13 (90 mg, 0.48 mmol) was added a solution of dimethylamine (2.9 M, 0.99 mL, 2.85 mmol) in anhydrous CH3OH, a solution of HCl (4.0 M, 0.24 mL, 0.95 mmol) in anhydrous 1,4-dioxane and sodium cyanoborohydride (30 mg, 0.48 mmol). The flask was purged with argon and stirred under an atmosphere of argon at room temperature for 24 h. The solution was adjusted to pH 2 with conc. HCl and the solvent was removed in vacuo. The residue was dissolved in water, washed with Et2O (3×10 mL), adjusted to pH 10 with NaOH(aq) (10 N), extracted with Et2O (3×20 mL), dried (Na2SO4), filtered and the solvent was removed in vacuo. The crude material was chromatographed on silica gel (CH3OH/CHCl3, 2.5/97.5, Rf=0.15) to afford the title compound 42 (57 mg, 55% yield) as a yellow oil: 1H NMR (CDCl3) δ 8.85 (br s, 1H), 8.48 (m, 1H), 7.82 (m, 1H), 7.28 (m, 1H), 7.21 (d, J=3.7 Hz, 1H), 6.91 (d, J=3.5 Hz, 1H), 3.65 (s, 2H) 2.31 (s, 6H); LRMS (ESI) m/z calcd for C12H15N2S [M+H]+ 219. found 219; m/z calcd for C10H8NS [M−N(CH3)2]+ 174. found 174; HRMS (ESI) m/z calcd for C12H15N2S [M+H]+ 219.0956. found 219.0955; HPLC>99% (tR=8.90 min, 55 (A):45 (B): 0.009 (C); tR=6.28 min, 55 (A):45 (B): 0.018 (C)).

1. customThe flask was purged with argon
2. customthe solvent was removed in vacuo
3. dissolutionThe residue was dissolved in water
4. washwashed with Et2O (3×10 mL)
5. extractionextracted with Et2O (3×20 mL)
6. dry with materialdried (Na2SO4)
7. filtrationfiltered
8. customthe solvent was removed in vacuo
9. customThe crude material was chromatographed on silica gel (CH3OH/CHCl3, 2.5/97.5, Rf=0.15)