Maximum quantity allowed is 999
We are proud to introduce the ring-closing metathesis of diallylmalonate ester using UltraCat as a catalyst.
To a solution of diethyl diallylmalonate (0.240 mL, 0.99 mmol) in anhydrous toluene (9.8 mL) was added a solution of UltraCat (0.1 mol%, 0.001 mmol, 1.0 mg) in toluene (0.1 mL) in one shot. The mixture was stirred at 40 °C under nitrogen for 2 hours. To the reaction mixture, was added 1,4-bis(3-isocyanopropyl)piperazine (0.5 mol%, 1.0 mg) to deactivate the catalyst. The solvent was removed under reduced pressure to give a crude of 1 (0.187 g, 89%) as a deep orange oil. The residue was passed through silica gel (eluent: hexane) to obtain 1 (0.143 g, 68%) as a light yellow oil.
Toluene was dried over molecular sieves 4A and was degassed by purging with nitrogen before use.
Preparation of catalyst stock solution: UltraCat (5.0 mg) was dissolved in dry degassed toluene (0.5 mL).
The reaction mixture was analyzed by gas chromatography and the reaction completed within 30 min.
Diethyl cyclopent-3-ene-1,1-dicarboxylate (1)
1H NMR (400 MHz, CDCl3); δ 5.60 (t, J =2.74 Hz, 2H), 4.20 (q, J =7.34 Hz, 4H), 3.01 (m, 4H), 1.25 (t, J=7.34 Hz, 4H).
13C NMR (101 MHz, CDCl3); δ 172.18, 127.75, 61.47, 58.78, 50.79, 13.98.
