Synthesis
Diethylene glycolamine (250 ml, 2340 mmol) and 2-methyltetrahydrofuran (1010 ml) were added to a 3-necked 3L flask equipped with an overhead stirrer, a dosing funnel, an N?inlet, and a temperature probe, and the mixture was cooled in an ice bath. A solution of 2-methyltetrahydrofuran (323 ml) of benzyl chloroformate (167 ml, 1125 mmol) was added slowly and dropwise over a period of 40 min, keeping the reaction temperature below 10 °C. The reaction mixture was stirred at room temperature for 1 hour after which a 1M hydrochloric acid solution of ethyl acetate (90 ml, 90 mmol) was added to it and stirring was continued for 30 minutes. The resulting white solid was removed by filtration through a filter pad lined with Solka Floc/Celite, and the filtrate was concentrated under vacuum to afford benzyl [2-(2-hydroxyethoxy)-ethyl]-carbamate (228 g, quantitatively) as a light yellow oil.
References
[1] Patent: WO2011/53614, 2011, A1. Location in patent: Page/Page column 9
[2] Organic and Biomolecular Chemistry, 2015, vol. 13, # 41, p. 10310 - 10323
[3] Patent: WO2011/19419, 2011, A1. Location in patent: Page/Page column 60
[4] Journal of the American Chemical Society, 2013, vol. 135, # 8, p. 2883 - 2886
[5] Patent: WO2014/145109, 2014, A1. Location in patent: Paragraph 0254
