Dimethyl Sulfoxide → (S)-6,7-Difluoro-10-[3-(2-methoxy-ethyl)-piperazin-1-yl]-2-methyl-4H-3-thia-4,9-diaza-benzo[f]azulene

Participants

Reaction Conditions

Reaction Steps

Add 6,7-difluoro-2-methyl-4H-3-thia-4,9-diaza-benzo[f]azulen-10-ylamine hydrochloride (65.0 g, 215 mmol) and 2-(2-methoxy-ethyl)-piperazine (96.3 g, 668 mmol) to a solution of DMSO (650 mL) and toluene (1300 mL) with stirring under nitrogen. Heat at gentle reflux (115° C.) for 2 days, and then allow cooling to ambient temperature. Remove most of the organic portion under reduced pressure, and then partition the residue between ethyl acetate (450 mL) and aqueous saturated ammonium chloride solution (450 mL). Separate the layers, and then extract the aqueous layer with ethyl acetate (3×200 mL). Extract the combined organic layers with brine (3×200 mL). Concentrate the organic layer under reduced pressure. Purify the crude product by flash chromatography, eluting with 90:10/methylene chloride:MeOH to give 56 g (66%) of the title compound. 1H NMR (400 MHz, DMSO-d6) δ 7.70 (s, 1H), 6.74 (m, 2H), 6.36 (s, 1H), 3.86 (bm, 2H), 3.39 (m, 2H), 3.23 (s, 3H), 2.88 (bd, 1H), 2.72 (bm, 3H), 2.44 (bt, 1H), 2.31 (s, 3H), 2.31 (bm, 1H), 1.53 (m, 2H). HRMS (ES) exact mass M+H calcd for C19H22F2N4OS 393.1561; found 393.1554.

Provenance & Evidence