Sodium Hydroxide → 3-Chloro-4-(methylsulfonyl)phenylhydrazine hydrochloride

To a stirred suspension of 3-chloro-4-(methylsulfonyl)aniline (3.0 g, 15.0 mmol, Ish. K. Khanna et al., J. Med. Chem. 40, 1619 (1997)) in 20% aqueous HCl (20 mL) was added dropwise a solution of sodium nitrite (1.1 g, 16.0 mmol) in water (20 mL) below −5° C. After stirring for 1 hour at that temperature, tin(II) chloride dihydrate in 20% aqueous HCl (20 mL) was added dropwise below −5° C. The resulting suspension was stirred for 1 h at room temperature. The mixture was basified with aqueous NaOH (pH=14) and extracted with CHCl3 (200 mL×2), dried over MgSO4, and concentrated in vacuo. The solid (5 g) was dissolved in 10% methanolic HCl (30 mL), and volatiles were removed by evaporation. The residue was washed with ethanol to give the title compound (1.3 g, 34%).

1. additionwas added dropwise below −5° C
2. extractionextracted with CHCl3 (200 mL×2)
3. dry with materialdried over MgSO4
4. concentrationconcentrated in vacuo
5. dissolutionThe solid (5 g) was dissolved in 10% methanolic HCl (30 mL)
6. customvolatiles were removed by evaporation
7. washThe residue was washed with ethanol

ORD record

ord-7b5733bcf51346aea8525ea421d188b1

Source dataset

uspto-grants-2005_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06949536B2