Stannous Chloride → (5-chloro-2-fluorophenyl)hydrazine

Temperature

-10 °C

5-Chloro-2-fluoroaniline (25 g, 172 mmol) was added to conc. hydrochloric acid (150 mL, 37%). The mixture was cooled (−10° C.) and a solution of sodium nitrite (11.9 g, 172 mmol) in water (193 mL) was added slowly (<−5° C.). This done, a solution of tin(II)chloride (118 g, 618 mmol) in conc. hydrochloric acid (116 mL) was added slowly (−6° C.). The mixture was stirred for 1 h, filtered through Celite® and the filter cake washed extensively with water. The filtrate was adjusted to pH 14 with conc. sodium hydroxide solution and the suspension extracted with diethylether. Organic phases were pooled, washed with brine, dried with MgSO4 and the solvent was removed in vacuo to yield the title compound as yellow solid (22.9 g, 83%), EI-MS: m/e=160.0 (M+).

1. filtrationfiltered through Celite®
2. washthe filter cake washed extensively with water
3. extractionthe suspension extracted with diethylether
4. washwashed with brine
5. dry with materialdried with MgSO4
6. customthe solvent was removed in vacuo

ORD record

ord-e4a6b88f241545f181fe5298bd26b572

Source dataset

uspto-grants-2007_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07253281B2