1-broMo-1-(4-chloro-3-(Methylsulfonyl)phenyl)propan-2-one synthesis

Yield:914382-89-1 80%

Reaction Conditions:

with bromine in 1,4-dioxane at 20; for 18 h;

Steps:

5.3

To a stirred solution of Stage 2 product (1.88g, 7.60mmol) in 1 ,4-dioxane (120ml) bromine (0.292ml, 5.72mmol) was added dropwise at r. t. giving a dark orange solution. Stirring was continued for 18 h. The reaction mixture was evaporated to dryness in vacuo avoiding heating above 3O⁰C during evaporation. The residue was re-dissolved in EtOAc (100ml) and washed with sat aq NaHCO₃ (20ml) followed by water (20ml). The EtOAc layer was dried (Na₂SO₄), filtered and concentrated in vacuo. Purification by flash chromatography (50% EtOAc / heptane) gave the title compound as a yellow oil (2.Og, 80%). LCMS purity 74%, m/z 325/327 [M⁺+H]; ¹H NMR (400 MHz, CDCI₃), δ: 2.35 (3H, s), 3.25 (3H, s), 5.35 (1 H, s), 7.50 (1H, d), 7.65 (1 H, dd), 8.05 (1 H, s).

References:

WO2006/117567,2006,A2 Location in patent:Page/Page column 84