Yield:-

Reaction Conditions:

with bromine in acetic acid at 20;

Steps:

89.1

To a solution of 30-1 (29.31 g, 200 mmol) in acetic anhydride (200 mL) was added bromine (32 g, 200 mmol) dropwise. After the addition, the mixture was stirred at room temperature overnight and then was poured into ice water. 100 mL of saturated aqueous NaHSO₃ aqueous was added. The precipitate was filtered and dried over Na₂SO₄ to afford 30-2 (48.Ig) as a white solid. LRMS: calc 223.9 and found: 224.9 [M+l].

References:

WO2011/19738,2011,A1 Location in patent:Page/Page column 183