Synthesis
The general procedure for the synthesis of N-Boc-L-homoserine from L-homoserine and di-tert-butyl dicarbonate was as follows: L-homoserine (4.76 g, 40 mmol) and sodium carbonate (Na2CO3, 8.48 g, 80 mmol) were dissolved in water (200 mL). To this solution, 1,4-dioxane (50 mL) was added and stirred for 5 minutes. Di-tert-butyl dicarbonate (Boc2O, 13.80 mL, 60 mmol) was slowly added to the solution under ice bath conditions, followed by stirring the reaction mixture overnight at room temperature. Upon completion of the reaction, the mixture was washed with petroleum ether to remove unreacted organic matter. Additional water was added to the mixture and the pH was adjusted to 2 with 2 mol/L hydrochloric acid (HCl) to induce precipitation of N-Boc-L-homoserine. The formed suspension was extracted with ethyl acetate (EtOAc), and the organic layers were combined and washed sequentially with water and brine. The organic layer was dried with anhydrous sodium sulfate (Na2SO4), filtered and concentrated to give the crude product (about 8.55 g).
References
[1] Journal of Organic Chemistry, 1986, vol. 51, # 26, p. 5047 - 5050
[2] Journal of Peptide Science, 2013, vol. 19, # 5, p. 308 - 314
[3] Journal of Organic Chemistry, 2008, vol. 73, # 8, p. 3212 - 3217
[4] Tetrahedron Letters, 2002, vol. 43, # 33, p. 5727 - 5729
[5] Journal of Organic Chemistry, 2003, vol. 68, # 23, p. 8853 - 8858
