Lithium Hexamethyldisilazide → N-(3-(2-(2-Chloropyrimidin-4-yl)acetyl)-2-fluorophenyl)-2,5-difluorobenzenesulfonamide

Temperature

0 °C

To a solution of methyl 3-(2,5-difluorophenylsulfonamido)-2-fluorobenzoate (44 g, 128 mmol (from a compilation of batches prepared as described above) in dry THF (500 mL) at −10° C., LiHMDS (1M in THF, 448 mmol, 448 mL) was added dropwise and the solution was allowed to stir for 1 h at 0° C. A solution of 2-chloro-4-methylpyrimidine (19.4 g, 154 mmol) in THF (50 mL) was then added dropwise to the solution of ester and base at 0° C. over 20 min. The solution was allowed to stir 1 h at rt. TLC showed the reaction was complete. The reaction was quenched by addition of the saturated aqueous NH4Cl (300 mL) at 0° C. The reaction mixture was extracted with EtOAc (500 mL×3). The combined organic layers were washed with water and brine successively, dried over Na2SO4, filtered and concentrated under reduced pressure to give the crude product, which was purified by flash column on silica gel, eluting with DCM. This solution was evaporated to obtain a solid. The orange solid was triturated with a small amount of EtOAc and filtered, rinsing with diethyl ether to give the title compound (18.6 g, 33.2% yield). 1H NMR (400 MHz, CDCl3) δ ppm 13.70-13.74 (br, 1H), 8.59 (d, J=5.29 Hz, 0.3H), 8.42 (d, J=5.51 Hz, 1H), 7.75-7.79 (m, 0.3H), 7.51-7.66 (m, 3.6H), 7.12-7.28 (m, 6.6H), 6.91 (d, J=5.51 Hz, 1H), 6.03 (s, 1H), 4.37 (s, 0.6H). MS (ES+): 442 [M+H]+

1. customat −10° C.
2. stirringto stir 1 h at rt
3. customThe reaction was quenched by addition of the saturated aqueous NH4Cl (300 mL) at 0° C
4. extractionThe reaction mixture was extracted with EtOAc (500 mL×3)
5. washThe combined organic layers were washed with water and brine successively
6. dry with materialdried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated under reduced pressure
9. customto give the crude product, which
10. customwas purified by flash column on silica gel
11. washeluting with DCM
12. customThis solution was evaporated
13. customto obtain a solid
14. customThe orange solid was triturated with a small amount of EtOAc
15. filtrationfiltered
16. washrinsing with diethyl ether

ORD record

ord-791d44abd3794711846306de7e08b0f9

Source dataset

uspto-grants-2014_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08642759B2