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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 2254122Generated: November 2, 2026

Phosphorus oxychloride → 4-Chloro-2-methyl-5,6,7,8-tetrahydroquinazoline

https://huagongshe.com/reaction/2254122

Reaction equation

Participants

RoleNameHCIDCharge
ReactantPhosphorus oxychlorideHCID 24813—
ReactantDiethylether waterHCID 21584184—
Reactant4(3H)-Quinazolinone, 5,6,7,8-tetrahydro-2-methyl-HCID 135431271—
CatalystN,N-DimethylanilineHCID 949—
SolventTolueneHCID 1140—
Product4-Chloro-2-methyl-5,6,7,8-tetrahydroquinazolineHCID 1974420795%

Reaction Steps

To a mixture of 4.5 mL of phosphorus oxychloride and 20 drops of dimethylaniline in 50 mL of toluene was added 4.2 g of 5,6,7,8-tetrahydro-2-methyl-4-quinazolone. The resulting mixture was refluxed for 3 hours and then cooled to room temperature. The reaction mixture was poured into a ice cold aqueous potassium carbonate. After stirring for 5 minutes the mixture was added to diethyl ether/water. The organic layer was recovered washed with brine, dried over anhydrous magnesium sulfate, filtered and evaporated to yield a yellow oil. This oil was purified on silica to yield the desired compound as a light yellow solid (4.45 g, 95%): 1H NMR (DMSO-d6, 300 MHz) δ 2.78 (m, 2H), 2.64 (m, 2H), 2.50 (s, 3H), 1.78 (m, 4H).

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS05234936
Source datasetuspto-grants-1993_08
ORD IDord-5f538b3607604f5e8de28b139735b8bd
Source noteuspto-grants-1993_08