Diethyl Malonate → Diethyl 2-(benzyloxyhexyl)malonate

Participants

Reaction Steps

To sodium metal (1.32 g, 0.0573 mol) dissolved in dry ethanol (150 ml) under argon at room temperature was added diethyl malonate (14.13 g, 0.088 mol) over a period of 10 minutes and the solution left for 2 hours. B1 (10.0 g 0.044 mol) was then added dropwise over 2 hours and this solution heated at reflux overnight. Excess salts were quenched by the addition of 50 ml of water and the total solvent volume reduced to 50-100 ml. Diethyl ether (100 ml) and water (50 ml) were added and the aqueous layer extracted 3 times with diethyl ether. The organic fractions were combined, dried (K2CO3), and the solvent removed to yield the crude product as a yellow oil. Distillation of the oil (0.5 mBar, 220° C.) gave the title compound (10.52 g, 68%) as a colourless viscous oil. δH (CDCl3) 1.32 (6H, t, Me), 1.43 (6H, br s, (CH2)3CH2CH), 1.69 (2H, p, CH2CH2O), 1.99 (2H, q, CH2CH), 3.39 (1H, t, CH), 3.53 (2H, t, CH2OCH2Ph), 4.25, 4.28 (4H, 2×q, OCH2Me), 4.57 (2H, s, CH2Ph), 7.3-7.4 (5H, m, Ph). δC (CDCl3) 13.9 (2 C, Me), 25.7 (1 C, CH2(CH2)2CH), 27.1 (1 C, CH2(CH2)2O), 28.5 (1 C, CH2CH2CH), 28.9 (1 C, CH2CH2O), 29.5 (1 C, CH2CH), 51.8 (CHCO2Et), 61.0 (2C, OCH2Me), 70.1, 72.7 (2C, CH2OCH2), 127.3 (1C, CH(CH)2C), 127.4 (2C, CGC), 128.1 (2C, CHCHC), 138.5 (1C, CCH2O) 169.3 (2C, CO2).

Provenance & Evidence