[Synthesis]
A hexane solution of n-butyllithium (n-BuLi, 2.80 mL, 2.60 M, 7.27 mmol) was slowly added dropwise to a tetrahydrofuran (THF, 7.5 mL) solution of 3-butyn-1-ol (0.50 mL, 6.61 mmol) at -78 °C. The reaction mixture was kept at -78 °C for 5 min before warming up to 0 °C and continued stirring for 30 min. Subsequently, a solution of p-Toluenesulfonyl chloride (p-TsCl, 1.51 g, 7.93 mmol) in THF (8 mL) was added and the reaction continued to be stirred at 0 °C for 30 min. Upon completion of the reaction, the reaction was quenched by the addition of water (2 mL) and the mixture was extracted with ether (Et2O, 3 × 10 mL). The organic phases were combined, dried with anhydrous sodium sulfate (Na2SO4), and concentrated under reduced pressure to remove the solvent to afford 3-butynyl p-toluenesulfonate (1.41 g, 95% yield) as a light yellow oil. The product was confirmed by nuclear magnetic resonance hydrogen spectroscopy (1H NMR, 400 MHz, CDCl3): δ 7.78 (d, J = 8.0 Hz, 2H), 7.33 (d, J = 8.0 Hz, 2H), 4.08 (t, J = 7.1 Hz, 2H), 2.53 (dt, J = 7.1, 2.6 Hz, 2H), 2.43 (s, 3H), 1.95 ( t, J = 2.6 Hz, 1H); nuclear magnetic resonance carbon spectrum (13C NMR, 100 MHz, CDCl3): δ 145.0, 132.7, 129.9, 127.9, 78.3, 70.7, 67.4, 21.6, 19.4; infrared spectra (IR, pure): 3290, 2962, 2919, 1598, 1359, 1190, 1176, 980, 904, 815 cm-1; mass spectra (ESI): m/z 247.0399 [C11H12O3S (M+23) theoretical value 247.0400], 471 (base), 247, 225. |
[References]
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[2] Synlett, 2001, # 12, p. 1971 - 1973
[3] Tetrahedron Letters, 2011, vol. 52, # 43, p. 5589 - 5592
[4] Organic and Biomolecular Chemistry, 2012, vol. 10, # 15, p. 3080 - 3091
[5] Chemical Communications, 2010, vol. 46, # 30, p. 5476 - 5478 |