A Publication
of Reliable Methods
for the Preparation
of Organic Compounds
Annual Volume
Org. Synth. 1997, 74, 205
DOI: 10.15227/orgsyn.074.0205
Submitted by Peter Wipf and Wenjing Xu1.
Checked by Thomas Wynn and Louis S. Hegedus.
1. Procedure

Caution! Dialkylzinc compounds, especially in undiluted form, are pyrophoric and must not be allowed to come into contact with air or moisture. These compounds should only be handled by individuals trained in their proper and safe use. [Note added January 2011]

A. tert-Butyl(but-3-ynyloxy)diphenylsilane. A dry, 250-mL, round-bottomed flask is fitted with a rubber septum and a magnetic stirring bar. The flask is charged with 3-butyn-1-ol (2.1 g, 30 mmol) (Note 1) and dry dichloromethane (60 mL) (Note 2). After addition of 8.5 g (31 mmol) of tert-butyldiphenylchlorosilane (Note 3), the reaction flask is immersed in a water bath and imidazole (2.86 g, 42 mmol) is added in one portion followed by 4-dimethylaminopyridine (0.37 g, 3 mmol). The water bath is removed and the reaction mixture is stirred at room temperature overnight. The white precipitate is filtered through a sintered glass funnel (`M' frit). The precipitate is washed with cold dichloromethane (50 mL). The combined filtrates are transferred to a 500-mL separatory funnel and washed with 1 M aqueous hydrochloric acid solution (50 mL) and water (100 mL), successively. The organic layer is dried over magnesium sulfate and concentrated by rotary evaporator. Bulb-to-bulb distillation of the residue (bp 150–152°C/1 mm) gives 8.90 g (96%) of tert-butyl(but-3-ynyloxy)diphenylsilane as a colorless oil (Note 4).
B. 1-[(tert-Butyldiphenylsilyloxy)]-dec-3-en-5-ol. A flame-dried, 250-mL, round-bottomed flask equipped with a gas inlet stopcock (Figure 1) is fitted with a rubber septum and a magnetic stirring bar, and flushed with nitrogen. The flask is charged with tert-butyl(but-3-ynyloxy)diphenylsilane (5.55 g, 18 mmol) and dry dichloromethane (60 mL), immersed in a cold water bath and stirred. Within 20 min, 5.10 g (19.8 mmol) of zirconocene hydrochloride (Note 5) is added in five portions. The water bath is removed and the reaction mixture is stirred at room temperature until a homogenous solution forms. The resulting golden-yellow solution is stirred for another 20 min (Note 6) and then cooled to −60°C. By syringe, dimethylzinc (2.0 M solution in toluene, 10.4 mL, 20.8 mmol) (Note 1) is added dropwise over 45 min while the bath temperature is kept at −60°C. The resulting orange-yellow solution is stirred for an additional 10 min at −60°C after the addition is completed. The reaction flask is immersed in an ice bath, and a solution of 2.16 g (21.6 mmol) of hexanal (Note 1) in dry dichloromethane (10 mL) is added via syringe over 45 min. The reaction mixture is stirred at 0°C for another 6 hr. The yellow solution is poured slowly into a beaker containing ice-cold aqueous 5% sodium bicarbonate solution (200 mL) and vigorous stirring is continued at room temperature until gas evolution subsides. The mixture is transferred to a 1-L separatory funnel and is extracted with diethyl ether (3 × 200 mL) (Note 7). The combined extracts are washed with a saturated aqueous sodium chloride solution (300 mL) and dried over sodium sulfate. The cloudy solution is filtered through a pad of Florisil (Note 8) loaded on a sintered glass funnel (`M' frit). The clear filtrate solution is concentrated by rotary evaporator. The residue is layered on a column of silica gel (150 g, column diameter: 6.0 cm) and eluted (ethyl acetate/hexane, 1:30 to 1:15 as eluents) to give 4.90 g (66%) of 1-[(tert-butyldiphenyl-silyl)oxy]-dec-3-en-5-ol as a colorless oil (Note 9).
Figure 1
Figure 1
2. Notes
1. 3-Butyn-1-ol, dimethylzinc and hexanal were obtained from Aldrich Chemical Company, Inc., and used without purification.
2. Solvent grade dichloromethane was dried over calcium hydride, refluxed and distilled freshly before use.
3. tert-Butyldiphenylchlorosilane was obtained from United Chemical Technologies, Inc. or Aldrich Chemical Company, Inc., and used without purification.
4. The product has the following spectral properties: 1H NMR (300 MHz, CDCl3) δ: 1.06 (s, 9 H), 1.95 (t, 1 H, J = 2.6), 2.45 (dt, 2 H, J = 7.1, 2.7), 3.79 (t, 2 H, J = 7.1), 7.36–7.46 (m, 6 H), 7.67–7.70 (m, 4 H).
5. Zirconocene hydrochloride was prepared according to Buchwald's procedure2 and stored in a Schlenk filter flask under argon in a freezer at −20°C or obtained from Aldrich Chemical Company, Inc., and used without further purification.
6. The reaction is conveniently monitored by TLC (silica gel, 4:1 hexane-ethyl acetate) with anisaldehyde stain (alkyne stains as a red spot, while the hydrozirconation product shows a blue color).
7. Significant amounts of white foam form between the ether and aqueous layers during extraction. Separation of these layers can be improved by the addition of 1–2 spoonfuls of solid sodium chloride.
8. Florisil (100–200 mesh) was obtained from Fisher Scientific Company.
9. The product has the following spectral data: IR (neat) cm−1: 3350, 2912, 1454, 1417, 1099, 733, 698, 609; 1H NMR (300 MHz, CDCl3) δ: 0.88 (t, 3 H, J = 6.7), 1.05 (s, 9 H), 1.34–1.51 (m, 9 H), 2.26–2.33 (m, 2 H), 3.71 (t, 2 H, J = 6.6), 4.00–4.03 (m, 1 H), 5.49 (dd, 1 H, J = 15.5, 6.8), 5.64 (dt, 1 H, J = 15.5, 6.7), 7.35–7.46 (m, 6 H), 7.66–7.69 (m, 4 H); 13C NMR (CDCl3) δ: 14.1, 19.2, 22.6, 25.2, 26.9, 31.8, 35.6, 37.2, 63.6, 73.1, 127.7, 128.2, 129.6, 133.9, 135.2, 135.6; MS (EI) m/e (relative intensity) 353 ([M-tert-butyl]+, 4), 335 (20), 229 (25), 199 (100), 135 (20), 91 (15), 57 (10); HRMS (EI) m/e calcd. for C22H29O2Si (M-C4H9): 353.1937, found: 353.1833.
Handling and Disposal of Hazardous Chemicals
The procedures in this article are intended for use only by persons with prior training in experimental organic chemistry. All hazardous materials should be handled using the standard procedures for work with chemicals described in references such as "Prudent Practices in the Laboratory" (The National Academies Press, Washington, D.C., 2011 www.nap.edu). All chemical waste should be disposed of in accordance with local regulations. For general guidelines for the management of chemical waste, see Chapter 8 of Prudent Practices.
These procedures must be conducted at one's own risk. Organic Syntheses, Inc., its Editors, and its Board of Directors do not warrant or guarantee the safety of individuals using these procedures and hereby disclaim any liability for any injuries or damages claimed to have resulted from or related in any way to the procedures herein.
3. Discussion
Organometallic derivatives of zirconium(IV) are readily obtained by hydrozirconation of alkenes and alkynes with Cp2ZrHCl (Schwartz reagent). Because of the relatively low reactivity of the resulting organozirconocenes, transmetalation protocols are frequently applied for further carbon-carbon formation.3 4 Transmetalation of alkenylzirconocenes to the corresponding organozinc compounds occurs rapidly at low temperature in the presence of stoichiometric amounts of commercially available dimethyl- or diethylzinc. Subsequent addition of aldehydes provides an in situ protocol for the conversion of alkynes into allylic alcohols in good to excellent yields.5 Compared to standard organometallic methods applying lithium or Grignard reagents for this transformation, the use zirconocenes tolerates the presence of a wide range of functional groups in the substrate (Table). The zirconium → zinc transmetalation is related in scope to the boron → zinc transmetalation, which can also be applied for the conversion of alkynes to allylic alcohols.6 7



Time (h)


yield (%)


















# On 5 g scale, this product was isolated in 68% yield.

References and Notes
  1. Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260.
  2. Buchwald, S. L.; LaMaire, S. J.; Nielsen, R. B.; Watson, B. T.; King, S. M. Org. Synth., Coll. Vol. IX 1998, 162
  3. Labinger, J. A. In "Comprehensive Organic Synthesis"; Trost, B. M.; Fleming, I., Eds.; Pergamon: Oxford, 1991; Vol. 8; pp 667–702;
  4. Wipf, P. Synthesis 1993, 537.
  5. Wipf, P.; Xu, W. Tetrahedron Lett. 1994, 35, 5197.
  6. Srebnik, M. Tetrahedron Lett. 1991, 32, 2449;
  7. Oppolzer, W.; Radinov, R. N. J. Am. Chem. Soc. 1993, 115, 1593.

Chemical Abstracts Nomenclature (Collective Index Number);
(Registry Number)

zirconocene hydrochloride

dimethyl- or diethylzinc

hydrochloric acid (7647-01-0)

ethyl acetate (141-78-6)

diethyl ether (60-29-7)

sodium bicarbonate (144-55-8)

sodium chloride (7647-14-5)

sodium sulfate (7757-82-6)

nitrogen (7727-37-9)

PhCHO (100-52-7)

toluene (108-88-3)

zinc (7440-66-6)

dichloromethane (75-09-2)

lithium (7439-93-2)

magnesium sulfate (7487-88-9)

Imidazole (288-32-4)

hexane (110-54-3)


argon (7440-37-1)


calcium hydride (7789-78-8)

3-butyn-1-ol (927-74-2)

Hexanal (66-25-1)

4-dimethylaminopyridine (1122-58-3)

tert-butyldiphenylchlorosilane (58479-61-1)

1-[(tert-BUTYLDIPHENYLSILYL)OXY]-DEC-3-EN-5-OL (190072-44-7)


dimethylzinc (544-97-8)