Reaction #1553

Reaction equation

ether

water

5,6-diethyl-2-[3-(2-dioxolanyl)phenyl]-3-propargyl-4(3H)-pyrimidinone

hydrochloric acid

→

5,6-diethyl-2-(3-formylphenyl)-3-propargyl-4(3H)-pyrimidinone

Yield 86.4%

Solvents

hexane

ethyl acetate

ethyl acetate

Conditions

Workup

1. 1
   workup.ADDITIONwere added to the reaction mixture
2. 2
   OtherThe layers were separated
3. 3
   Extractionthe aqueous layer was extracted twice with 50 mL of ether
4. 4
   Dryingdried over MgSO4
5. 5
   Concentrationconcentrated

Procedure

To a solution of 2.3 g (6.8 mmol) of 5,6-diethyl-2-[3-(2-dioxolanyl)phenyl]-3-propargyl-4(3H)-pyrimidinone in 1 mL of ethyl acetate was added 50 mL of 6M hydrochloric acid and the mixture was stirred for 4 hours. The reaction was followed by gas chromatography and TLC(20% ethyl acetate in hexane). Upon completion of reaction, 75 mL of ether and 150 mL of water were added to the reaction mixture. The layers were separated and the aqueous layer was extracted twice with 50 mL of ether. The organic layers were combined, dried over MgSO4 and concentrated to yield 1.73 g of 5,6-diethyl-2-(3-formylphenyl)-3-propargyl-4(3H)-pyrimidinone (Compound 69) as a yellow oil (86%), which solidified on standing. Mp.=82°-86° C. 1H-NMR (CDCl3) δ 1.25(6H,m), 2.4(1H,t), 2.65(4H,q), 4.6(2H,d), 7.7(1H,t), 8.05(2H,m), 8.25(1H,s), 10.15(1H,s).

Source