Potassium Phosphate, Tribasic → Tert-butyl 4-(5-(2-(3-ethylureido)-6-fluorobenzo[d]thiazol-5-yl)pyrimidin-2-yl)piperazine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

A solution of 1-(5-bromo-6-fluoro-benzothiazol-2-yl)-3-ethyl-urea (0.05 g, 0.15 mmol), tert-butyl 4-(5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyrimidin-2-yl)piperazine-1-carboxylate (0.12 g, 0.31 mmol) and K3PO4 (0.13 g, 0.61 mmol) in DMF-H2O (5.0 mL, 3:2) was degassed by flushing with nitrogen for 15 min. Dichlorobis(triphenylphosphine)-palladium(II) (0.021 g, 0.03 mmol) was then added to the reaction mixture followed by degassing with nitrogen for another 15 min. The resulting reaction mixture was then heated to 95-100° C. for 2 h. After the completion of the reaction (TLC monitoring), the reaction mixture was cooled to room temperature and poured onto ice-cold water followed by extraction with EtOAc (2×50 mL). The combined organics was washed with brine, dried (Na2SO4), filtered and concentrated under reduced pressure. The crude was then purified over silica gel (100-200 M, 1.60% MeOH-DCM) to obtain the desired product (0.015 g, 20%). 1H-NMR (400 MHz, DMSO-d6): δ 1.08 (t, J=7.20 Hz, 3H), 1.43 (s, 9H), 3.20 (m, 2H), 3.42 (br s, 4H), 3.79 (br s, 4H), 6.71 (br s, 1H), 7.76 (d, J=6.80 Hz, 1H), 7.92 (d, J=10.40 Hz, 1H), 8.62 (s, 2H) and 10.74 (br s, 1H). MS: 502.27 (M+H)+. Qualitative HPLC Purity (Acquity BEH C-18, 100×2.1 mm, 272 nm): 99.21% (Rt=6.51 min).

Provenance & Evidence