methyl 11-azidoundecanoate

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Crunched sodium hydroxide (709 mg, 17.7 mmol) was added to a solution of methyl 11-azidoundecanoate (4.03 g, 17.7 mmol) in methanol (75 ml). The reaction mixture was stirred for 16 h at room temperature. Water (50 ml) was added. The mixture was acidified to pH 2 by addition of a 10% aqueous solution of sodium hydrogensulphate and was extracted with ethyl acetate (3×50 ml). The combined organic layers were dried over sodium sulphate. The solvent was removed in vacuo. The residue was dissolved in methanol (50 ml). Crunched sodium hydroxide (1.42 g, 35.4 mmol) was added. The reaction mixture was stirred at room temperature for 16 h. Water (50 ml) was added. The mixture was acidified to pH 2 by addition of a 10% aqueous solution of sodium hydrogensulphate and was extracted with ethyl acetate (3×50 ml). The combined organic layers were dried over sodium sulphate. The solvent was removed in vacuo to give 3.13 g of 11-azidoundecanoic acid. was extracted with ethyl acetate (3×50 ml) The combined organic layers were dried over sodium sulphate The solvent was removed in vacuo The residue was dissolved in methanol (50 ml) The reaction mixture was stirred at room temperature for 16 h was extracted with ethyl acetate (3×50 ml) The combined organic layers were dried over sodium sulphate The solvent was removed in vacuo

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Sodium azide (4.66 g, 72 mmol) and tetrabutylammonium iodide (66 mg, 0.18 mmol) were successively added to a solution of methyl 11-bromoundecanoate (commercially available at Aldrich, 5.00 g, 17.9 mmol) in N,N-dimethylformamide (50 ml). The reaction mixture was heated to 60° C. for 16 h and cooled to room temperature. It was diluted with water (200 ml) and extracted with ethyl acetate (200 ml). The aqueous phase was washed with water (2×200 ml). The organic phase was dried over sodium sulphate. The solvent was removed in vacuo to give 4.28 g of methyl 11-azidoundecanoate. cooled to room temperature extracted with ethyl acetate (200 ml) The aqueous phase was washed with water (2×200 ml) The organic phase was dried over sodium sulphate The solvent was removed in vacuo

Conditions: temp:66.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 13.3 g of methyl 11-bromoundecanoate and 3.12 g of sodium azide in 50 mL of DMSO was heated at 66° C. under nitrogen for 2 days. The reaction mixture was cooled down and mixed with 200 mL of ice water. The aqueous layer was extracted with ether (1×100 mL, subsequently 3×50 mL). The organic layers were combined, washed twice with 25 mL of brine and dried over Na2SO4. Removal of the solvents in vacuo gave 11.2 g of a yellow oil. Purification by column chromatography (silica gel; petroleum ether (40-60° C.)/ether=9:1 (v/v)) gave 10.94 g of the pure product as a colorless oil, which was stored at 4° C. to prevent degradation. 1H NMR (300 MHz, CDCl3): δ 3.65 (s, 3H); 3.24 (t, 2H, J=7.0 Hz); 2.29 (t, 2H, J=7.5 Hz); 1.65-1.53 (m, 2H); 1.42-1.21 (m, 14H) ppm. 13C NMR (75 MHz, CDCl3): δ 174.24; 51.44; 51.37; 34.04; 29.35; 29.27; 29.15; 29.07; 28.80; 26.66; 24.89 ppm. IR (neat, cm−1): 2929 (m); 2856 (m); 2096 (s); 1741 (s). The reaction mixture was cooled down The aqueous layer was extracted with ether (1×100 mL, subsequently 3×50 mL) washed twice with 25 mL of brine dried over Na2SO4 Removal of the solvents in vacuo