Synlett 2019; 30(02): 235-239
DOI: 10.1055/s-0037-1610677
letter
© Georg Thieme Verlag Stuttgart · New York

Iron-Catalyzed Synthesis of (E)-β-Vinylsilanes via a Regio- and Stereoselective Hydrosilylation from Terminal Alkynes

Zhi-Kai Liu §
,
Guo-Liang Zhang §
,
Ding-Chang Li
,
Ying Yang
,
Li Chen
,
Zhuang-Ping Zhan*
Financial support from the National Natural Science Foundation of China (no. 21772166) and the NFFTBS (no. J1310024) is gratefully acknowledged.
Further Information

Publication History

Received: 10 October 2018

Accepted after revision: 16 November 2018

Publication Date:
17 December 2018 (online)


§ Authors contributed equally to this work.

Abstract

A concise strategy for the synthesis of vinylsilanes from an iron-catalyzed regio- and stereoselective hydrosilylation of terminal alkynes has been developed. The catalyst and reagents are commercially available and easy to handle, providing a simple and practical method for iron-catalyzed anti-Markovnikov hydrosilylation with a good functional group tolerance.

Supporting Information

 
  • References and Notes

  • 1 Elke L, Dieter S. Chem. Rev. 1995; 95: 1375
  • 7 Field LD, Ward AJ. J. Organomet. Chem. 2003; 681: 91
  • 14 Synthesis of (E)-β-Vinylsilanes; General ProcedureIn a nitrogen filled Schlenk tube, FeCl2 (2 mol%), Xantphos (2 mol%), NaBHEt3 (4 mol%), and ether (2 mL) were added and the mixture was stirred at 50 °C for 10 minutes, then alkyne (1.0 mmol) and phenylsilane (1.1 mmol) were added under N2. The reaction mixture was stirred at 50 °C. Upon completion, the solvent was removed by vacuum and the crude residue was purified by silica gel column chromatography to afford the corresponding product 3(eluent: petroleum ether/EtOAc, 100:1).(E)-But-1-en-1-yl(phenyl)silane (3a)Yield: 82% (201.7 mg); colorless liquid; 1H NMR (400 MHz, CDCl3): δ = 7.66–7.68 (m, 2 H), 7.44–7.48 (m, 3 H), 6.46 (dt, J 1 = 18.5 Hz, J 2 = 6.4 Hz, 1 H), 5.79–5.85 (m, 1 H), 4.65 (d, J = 3.2 Hz, 2 H), 2.25–2.31 (m, 2 H), 1.49–1.54 (m, 2 H), 1.38–1.41 (m, 10 H), 0.99 (t, J = 6.8 Hz, 3 H); 13C NMR (125 MHz, CDCl3): δ = 154.2, 135.3, 132.4, 129.5, 128.0, 119.8, 36.9, 31.9, 29.4, 29.3, 29.2, 28.4, 22.7, 14.1; IR (film): 3065, 2131, 1615 cm–1; HRMS (ESI): m/z [M+H]+ calcd for C16H27Si+: 247.1877; found: 247.1876.(E)-6-(Phenylsilyl)hex-5-enenitrile (3j)Yield: 44% (88.4 mg); colorless liquid; 1H NMR (400 MHz, CDCl3): δ = 7.56–7.58 (m, 2 H), 7.36–7.44 (m, 3 H), 6.28 (dt, J 1 = 18.5 Hz, J 2 = 6.3 Hz, 1 H), 5.81–5.88 (m, 1 H), 4.55 (d, J = 3.0 Hz, 2 H), 2.33–2.38 (m, 4 H), 1.77–1.85 (m, 2 H). 13C NMR (100 MHz, CDCl3): δ = 150.3, 135.3, 131.6, 129.8, 128.1, 123.1, 119.4, 35.3, 24.1, 16.5; IR (film): 3065, 2234, 2132, 1615 cm–1; HRMS (ESI): m/z [M+H]+ calcd for C12H16NSi+: 202.1047; found: 202.1045.(E)-tert-Butyldimethyl((6-(phenylsilyl)hex-5-en-1-yl)oxy)silane (3l)Yield: 70% (224 mg); colorless liquid; 1H NMR (400 MHz, CDCl3): δ = 7.58–7.61 (m, 2 H), 7.37–7.42 (m, 3 H), 6.38 (dt, J1 = 18.4 Hz, J2 =6.3 Hz, 1 H), 5.73–5.79 (m, 1 H), 4.55 (d, J = 3.2 Hz, 2 H), 3.64 (t, J = 6.3 Hz, 2 H), 2.22–2.27 (m, 2 H), 1.50–1.57 (m, 4 H), 0.92 (s, 9 H), 0.07 (s, 6 H). 13C NMR (125 MHz, CDCl3): δ = 153.8, 135.3, 132.3, 129.6, 128.0, 120.1, 63.0, 36.6, 32.3, 26.0, 24.7, 18.4, –5.3; IR (film): 3062, 2132, 1615 cm–1; HRMS (ESI): m/z [M+H]+ calcd for C18H33OSi2 +: 321.2065; found: 321.2067.(E)-(4-Ethylstyryl)(phenyl)silane (3o)Yield: 64% (152.3 mg); colorless liquid; 1H NMR (500 MHz, CDCl3): δ = 7.62–7.64 (m, 2 H), 7.37–7.42 (m, 5 H), 7.13–7.19 (m, 3 H), 6.45 (d, J = 19.0 Hz, 1 H), 4.69 (s, 2 H), 2.65 (q, J = 7.5 Hz, 2 H), 1.24 (t, J = 7.6 Hz, 3 H). 13C NMR (125 MHz, CDCl3): δ = 149.3, 145.1, 135.5, 135.4, 131.9, 129.8, 128.1, 128.1, 126.7, 118.0, 28.7, 15.5; IR (film): 3065, 2132, 1599 cm–1; HRMS (ESI): m/z [M+H]+ calculated for C16H19Si+: 239.1251; found: 239.1252.(E)-(4-Methoxystyryl)(phenyl)silane (3p)Yield: 60% (144 mg); colorless liquid; 1H NMR (400 MHz, CDCl3): δ = 7.65–7.70 (m, 2 H), 7.39–7.49 (m, 5 H), 7.18 (d, J = 18.9 Hz, 1 H), 6.89–6.94 (m, 2 H), 6.40 (dt, J 1 = 19.0 Hz, J 2 = 3.3 Hz, 1 H), 4.77 (d, J = 3.2 Hz, 2 H), 3.85 (s, 3 H). 13C NMR (100 MHz, CDCl3): δ = 160.1, 148.8, 135.5, 132.0, 130.8, 129.7, 128.1, 128.0, 116.4, 114.0, 55.3; IR (film): 3068, 2135, 1601 cm–1; HRMS (ESI): m/z [M+H]+ calcd for C15H17OSi+: 241.1044; found: 241.1045.(E)-(4-Fluorostyryl)(phenyl)silane (3q)Yield: 45% (102.6 mg); colorless liquid; 1H NMR (400 MHz, CDCl3): δ = 7.63–7.65 (m, 2 H), 7.39–7.45 (m, 5 H), 7.10 (d,J=18.9 Hz, 1 H), 7.02–7.06 (m, 2 H), 6.43 (dt, J 1 =18.9 Hz, J 2 = 3.2 Hz, 1 H), 4.70 (d, J = 3.1 Hz, 2 H). 13C NMR (100 MHz, CDCl3): δ = 163.0 (d, J = 248.8 Hz), 148.0, 135.5, 134.1, 131.5, 129.9, 128.3 (d, J = 8.2 Hz), 128.2, 119.2 (d, J = 2.0 Hz), 115.5 (d, J = 22.1 Hz); IR (film): 3068, 2137, 1601 cm–1; HRMS (ESI): m/z [M+H]+ calcd for C14H14FSi+: 229.0844; found: 229.0843