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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1709127Generated: November 3, 2026

Sodium Hydroxide → 5,7-Dichloro-2,3-dihydro-4-hydrazino-2-methylbenzofuran

https://huagongshe.com/reaction/1709127

Reaction equation

Participants

RoleNameHCIDCharge
ReactantSodium HydroxideHCID 14798—
ReactantStannous ChlorideHCID 24479—
ReactantSodium NitriteHCID 23668193—
Reactant4-Amino-5,7-dichloro-2,3-dihydro-2-methylbenzofuranHCID 53971178—
SolventHydrochloric AcidHCID 313—
SolventWaterHCID 962—
SolventSulfuric AcidHCID 1118—
Product5,7-Dichloro-2,3-dihydro-4-hydrazino-2-methylbenzofuranHCID 54549881—

Reaction Conditions

Temperature0 °C

Reaction Steps

2.19 g of 38A was suspended in 9 mL of concentrated H2SO4 and 9 mL of water at -5° C. A solution of 0.69 g of sodium nitrite in 4 mL of H2O was added slowly and the resulting solution was stirred at 0° C. for one hour. This solution was added slowly to a mixture of 4.51 g of tin (II) chloride in 15 mL of concentrated hydrochloric acid which was precooled to -10° C., so as to maintain -10° C. to -5° C. The mixture was slowly warmed to room temperature and stirred for 16 hours. With cooling, 50% sodium hydroxide solution was added to adjust the pH to 11. The mixture was extracted with ether. The extract was washed with water, brine, dried (MgSO4) and stripped of solvent to leave crude 5,7-dichloro-2,3-dihydro-4-hydrazino-2-methylbenzofuran (38B), as pale orange solid, m.p.: 59°-64° C.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS04948418
Source datasetuspto-grants-1990_08
ORD IDord-8e89f35bc8874fb49d19d6a0154071de
Source noteuspto-grants-1990_08