Stannous Chloride → Ethyl 2-chloro-4-fluoro-5-hydrazinobenzoate hydrochloride

HRID 48488Notes

Reaction equation

HRID 48488 reaction equation
[NH2:1][C:2]1[C:3]([F:14])=[CH:4][C:5]([Cl:13])=[C:6]([CH:12]=1)[C:7]([O:9][CH2:10][CH3:11])=[O:8].[N:15]([O-])=O.[Na+].[Sn](Cl)Cl>Cl.O>[ClH:13].[Cl:13][C:5]1[CH:4]=[C:3]([F:14])[C:2]([NH:1][NH2:15])=[CH:12][C:6]=1[C:7]([O:9][CH2:10][CH3:11])=[O:8]

Participants

6

Reactant 3

HCID 24479Stannous ChlorideHCID 22508461Ethyl 5-amino-2-chloro-4-fluorobenzoateHCID 23668193Sodium Nitrite

Product 1

HCID 22508450Ethyl 2-chloro-4-fluoro-5-hydrazinobenzoate hydrochlorideYield 116%

Reagents, catalysts & solvents 2

HCID 313Hydrochloric AcidSolvent2×HCID 962WaterSolvent

Conditions

Temperature
0 °C

Procedure

Then, 19 g (87.4 mmol) of ethyl 5-amino-2-chloro-4-fluorobenzoate was dissolved in 120 ml of hydrochloric acid, followed by cooling to 0° C., to which a solution of 6.3 g (91.7 mmol) of sodium nitrite dissolved in 10 ml of water was added dropwise at 10° C. or lower. The mixture was stirred at 0° C. for 30 minutes and then cooled to −30° C., into which a solution of 58 g (0.31 mol) of anhydrous tin(II)chloride dissolved in 40 ml of hydrochloric acid was poured, followed by further stirring at 0° C. for 3 hours. The precipitated crystals were collected by filtration and then dried, which afforded 13.6 g (50.7 mmol) of crude ethyl 2-chloro-4-fluoro-5-hydrazinobenzoate hydrochloride.

Workup

  1. additionwas added dropwise at 10° C.
  2. additionwas poured
  3. stirringby further stirring at 0° C. for 3 hours
  4. filtrationThe precipitated crystals were collected by filtration
  5. customdried

Sources & evidence

ORD record
ord-1e53f4c2d1274f0eb6361fcb4485162c
Source dataset
uspto-grants-2004_03
Patent number
US06703503B2

Reaction notes

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