(Methoxycarbonylsulfamoyl)triethylammonium hydroxide → 2-[5-Methyl-1-(4-methylbenzyl)-1H-pyrazol-3-yl]-4-phenyl-4,5-dihydro-1,3-oxazole

Participants

Reaction Conditions

Reaction Steps

A mixture of N-[(1R)-2-hydroxy-1-phenylethyl]-5-methyl-1-(4-methylbenzyl)-1H-pyrazole-3-carboxamide (Step 1, 350 mg, 1.0 mmol) and carbomethoxysulfamoyltriethylammonium hydroxide inner salt (Burgess' reagent, 310 mg, 1.03 mmol) in THF (20 mL) was heated at 70° C. for 1 h. After being cooled to rt, the mixture was diluted with water (10 mL), and the organic phase was extracted with ethyl acetate (1×25 mL), washed with brine (1×25 mL), dried (Na2SO4), filtered, and concentrated to dryness. The crude was then purified with an ISCO CombiFlash Companion using gradient elution from 0% to 20% EtOAc in hexanes to afford the title compound as a yellow oil (230 mg, 69%): 1H NMR (300 MHz, DMSO-d6) δ 7.31-7.34 (m, 2H), 7.24-7.28 (m, 3H), 7.12 (d, 2H), 7.01 (d, 2H), 6.52 (s, 1H), 5.27-5.32 (m, 1H), 5.29 (s, 2H), 4.69-4.75 (m, 1H), 4.06-4.12 (m, 1H), 2.25 (s, 3H), 2.22 (s, 3H); ES-MS m/z 332.20, HPLC RT (Method B) 3.20 min.

Provenance & Evidence