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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 903326Generated: October 27, 2026

Hydrochloric Acid → Tetrazolo[1,5-a]quinazolin-5(1H)-one

https://huagongshe.com/reaction/903326

Reaction equation

Participants

RoleNameHCIDCharge
ReactantHydrochloric AcidHCID 313—
ReactantNitriteHCID 946—
ReactantNitrous AcidHCID 24529—
ReactantSodium NitriteHCID 23668193—
Reactant2-Hydrazinyl-3,4-dihydroquinazolin-4-oneHCID 135449613—
ProductTetrazolo[1,5-a]quinazolin-5(1H)-oneHCID 135703146—

Reaction Steps

2-Hydrazino-quinazolin-4-one (IIIb) (17.6 g; 0.1 mole), was suspended in 2 N-hydrochloric acid (78 ml; 0.156 mole) in a 600 ml beaker equipped with a thermometer and efficient stirrer. 15% w/v aqueous NaNO2 solution was added at such a rate that the temperature remained between 20° and 25° C., cooling with a water bath when necessary, until a small permanent excess of nitrous acid was present. The volume of the nitrite solution used was 63 ml (=9.45 g NaNO2 ; 0.137 mole). The reaction mixture was then stirred for 1 hour, filtered, and the solid washed acid free with water. After pulling as dry as possible on the filter, the product was dried completely in a vacuum desiccator over phosphorus pentoxide.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS04226994
Source datasetuspto-grants-1980_10
ORD IDord-e2258570ef4a46399e89948902e411df
Source noteuspto-grants-1980_10