But-3-ene-1-ol (Aldrich),
4-Dimethylaminopyridine (Avocado),
Triethylamine (Avocado),
Benzoic anhydride.

But-3-ene-1-ol (3.0 g, 42 mmol) was dissolved in dichloromethane (100 mL) and triethylamine (7.6 mL, 5.6 g, 55 mmol) was added followed by DMAP (50 mg). Benzoic anhydride (12.4 g, 55 mmol) was added and the resulting yellow solution allowed to stir for 6 hours after which time dilute HCl (2 M, 100 mL) was added. The organic phase was separated and washed with a further two portions of HCl (2 x 100 mL) and water (2 x 100 mL). The organic phase was separated, dried (MgSO₄), filtered and concentrated in vacuo. The crude product was purified by distillation (20 mm, bp. 82-84 ^oC) to yield the pure benzoate ester as a clear oil (4.8 g, 28 mmol, 65%).

We have performed this reaction twice and on a scale of 3-5 g of the alcohol. The reaction is not particularly sensitive to air, moisture etc. The addition of DMAP however accelerates the reaction significantly. Efficient cooling must therefore be used on the addition of DMAP to prevent overheating.

¹H NMR (300 MHz, CDCl₃) 8.05 (2H, br. d), 7.56 (1H, br. t), 7.44 (2H, br. t), 5.88 (1H, app. ddt), 5.17 (1H, d), 5.12 (1H, d), 4.37 (2H, t), 2.53 (2H, app. q).

Ramnauth, J.; Lee-Ruff, E.; Can.J.Chem., 77, 1999, 1245.