反応 #1559

反応方程式

trifluoroacetic anhydride

5-aminocarbonylmethyl-6-ethyl-2-phenyl-3-propargyl-4(3H)-pyrimidinone

Compound 275

5-aminocarbonylmethyl-6-ethyl-2-phenyl-3-propargyl-4(3H)-pyrimidinone

pyridine

→

6-ethyl-5-cyanomethyl-6-ethyl-2-phenyl-3-propargyl-4(3H)-pyrimidinone

収率 49.8%

溶媒

ether

THF

反応条件

後処理

1. 1
   workup.ADDITIONwas added
2. 2
   洗浄washed with 20 mL of saturated aqueous NaHCO3
3. 3
   乾燥dried over MgSO4
4. 4
   その他Removal of the solvent
5. 5
   workup.WAITleft 0.24 g of crude product as a yellow solid
6. 6
   洗浄Flash chromatography on 30 g of silica gel, eluting sequentially with 50, 75 and 100% ether in hexanes

実験手順

A stirred suspension of 0.25 g (0.85 mmol) of 5-aminocarbonylmethyl-6-ethyl-2-phenyl-3-propargyl-4(3H)-pyrimidinone (Compound 275) in 12 mL of THF was cooled in an icebath and 0.15 mL (1.9 mmol) of pyridine was added followed by 0.13 mL (0.92 mmol) of trifluoroacetic anhydride. The mixture was stirred in the ice bath for 4 h, diluted with 80 mL of ether, washed with 20 mL of saturated aqueous NaHCO3 and dried over MgSO4. Removal of the solvent left 0.24 g of crude product as a yellow solid. Flash chromatography on 30 g of silica gel, eluting sequentially with 50, 75 and 100% ether in hexanes afforded 0.13 g of 6-ethyl-5-cyanomethyl-6-ethyl-2-phenyl-3-propargyl-4(3H)-pyrimidinone (Compound 277) as a white solid, m.p. 178°-180° C. 1 H-NMR (CDCl3) 1.3(3H,t), 2.4(1H,t), 2.75(2H,q), 3.75(2H,s), 4.6(2H,d), 7.55(3H,m), 7.7(2H,m).

出典