To a solution of 3-fluoro-N-(4-methoxybenzyl)-4-nitro-N-(thiazol-2-yl)benzenesulfonamide (9.0 g, 21.2 mmol) in THF (80 mL) was added a THF solution of NaOSi(Me)3 (4.76 g, 42.5 mmoles, 1 M, Aldrich) at 0° C. and the resulting mixture was stirred at 25° C. for 2 h. After completion of the reaction (monitored by TLC), reaction mass was quenched with 1N HCl (70 mL). The organic compound was then extracted with EtOAc, washed with water, dried over sodium sulfate and concentrated to get the 9.20 g of crude material, 3-hydroxy-N-(4-methoxybenzyl)-4-nitro-N-(thiazol-2-yl)benzenesulfonamide as yellow semi-solid which was used for next step as is.
