Hexamethylphosphoramide → Dibenzyl 2-methylenepentanedioate

Participants

Reaction Conditions

Reaction Steps

Benzyl acrylate (500 g, 3 mol) was heated to 100° C. under an atmosphere of nitrogen. The heating was stopped and HMPT (10 g, 61 mmol) was added dropwise while maintaining an internal temperature of 135-145° C. Once addition was complete the mixture was cooled to room temperature and a slurry of silica with 5:1 Hex/EtOAc was added. The slurry was then transferred to a column containing a plug of dry silica. The column was then washed with 1:1 Hex/EtOAc and the solvent was collected and evaporated. The clear yellow liquid was distilled under high vacuum (200 μHg) to give an initial fraction of 8 g distilling at 45° C. and then the desired product at 180-185° C. (212 g, 42%) as a clear and colorless liquid. 1H NMR (CDCl3) 7.3 ppm (3, 10H); 6.2 ppm (s, 1H); 5.5 ppm (s, 1H); 5.2 ppm (s, 2H); 5.1 ppm (s,2H); 2.6 ppm (m, 4H).

Provenance & Evidence