Dimethyl Sulfate → HCID 86170751, compound

Participants

Reaction Steps

The crude nitrile 23 obtained above (79 g, 0.401 mol) is heated under reflux for 24 h with potassium hydroxide (31 g, 0.47 mol), 250 mL ethanol and 100 mL water. 300 mL water is added and most of the ethanol is distilled off. 200 mL n-propanol is added and the mixture is heated under reflux for 2 d. After cooling, 300 mL water is added and the mixture is extracted with 2×250 mL toluene. The toluene layers are washed with 250 mL water. The aqueous layers are evaporated, the last traces of water are removed at 100° C. (0.2 mmHg). The solid residue is stirred for 24 h with 300 mL DMF and 62 mL dimethyl sulfate (0.66 mol). The mixture is evaporated and to the residue there is added 500 mL toluene and 300 mL water. The layers are separated and the toluene layer is washed with 300 mL water. The aqueous layers are extracted with 250 mL toluene. The combined organic layers are dried and evaporated end the residue is purified by bulb-to-bulb distillation to give ester 24 (47.7 g, 0.207 mol, 52%) with bp 120° C. (0.2 mmHg). 1H-NMR (CCl4): δ 1.0-1.9 (m), 1.25 (s) and 1.30 (s) (13H), 2.2 (bt, 2H), 3.2-3.9 (m) and 3.6 (s) (7H).

Provenance & Evidence