t-Butyldiphenylsilylation of 3-Butyn-1-ol -- DMAP as Catalyst

P. Wipf and W. Xu, Org. Synth., 74, 205 (1997)

1. To a stirred solution of butyn-1-ol (2.1 g, 30 mmol) in dry dichloromethane (60 mL) is added tert-butyldiphenylchlorosilane (8.5 g, 31 mmol) and the resultant reaction mixture is immersed in a water bath.  Imidazole (2.86 g, 42 mmol) and DMAP (0.37 g, 3 mmol) are added and the reaction flask removed from the water bath.
2. The reaction mixture is stirred at room temperature overnight.
3. The white precipitate is removed by filtration through a sintered glass funnel and the precipitate is washed with cold dichloromethane (50 mL).  The combined filtrates are washed successively with 1 M hydrochloric acid (50 mL), and water (100 mL); the organic layer is dried (anhydrous magnesium sulfate), filtered and concentrated.  Bulb to bulb distillation of the residue affords tert-butyl(but-3-ynyloxy)diphenylsilane (8.90 g, 96%, b.p. 150-151°C at 1 mm.)