Hexamethylphosphoramide → 2-Tetradec-6-ynoxy-tetrahydro-pyran

Beteiligte Stoffe

Reaktionsschritte

1-Nonyne 11 (1.0 g, 8.06 mmol) in THF (20 ml) was treated with n-BuLi (1.7 M in hexanes, 6.6 ml, 0.011 mmol) at 0° C. and the resulting pale yellow solution stirred for a 15 min. HMPA (15 ml) was then added and the mixture stirred for a further 15 min at 0° C. To the resultant dark yellow/orange solution was then added 10 (3.6 g, 0.0121 mol) at 0° C. which resulted in a immediate colour change in the solution to light yellow. This light yellow solution was stirred at r.t. overnight at which stage it was triturated with water and extracted with hexanes. The hexane extract were well washed with water, dried (MgSO4) and concentrated invacuo to afford a light yellow residue which was purified by flash column chromatography (eluent—8.5% EtOAc in hexanes) to yield a the pure 12 (1.6 g, 70%); δH(270 MHz, CDCl3); 0.86 (3H, t, J 6.2), 1.15-1.85 (13H, m), 2.11 (4H, m), 3.30-3.55 (2H, m), 3.69-3.90 (2H, m) and 4.56 (1H, m); δC(67.5 MHz, CDCl3) 14.17, 18.82, 18.82, 19.74, 22.71, 25.57, 25.57, 28.91, 28.91, 29.08, 29.24, 29.38, 30.49, 30.84, 31.84, 62.40, 62.40, 67.57, 67.57, 98.90. MS (EI) 295 (M+H)+; HRMS: Found 295.2616 [M+H]+. Calc. for C19H35O2: 295.263706 [M+H]+.

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