Synlett 2012; 23(17): 2567-2571
DOI: 10.1055/s-0032-1317179
letter
© Georg Thieme Verlag Stuttgart · New York

Conjugate Hydrocyanation of Aromatic Enones Using Potassium Hexacyanoferrate(II) as an Eco-Friendly Cyanide Source

Zheng Li*
College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, P. R. of China   Fax: +86(931)7971989   Email: lizheng@nwnu.edu.cn
,
Chenhui Liu
College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, P. R. of China   Fax: +86(931)7971989   Email: lizheng@nwnu.edu.cn
,
Yupeng Zhang
College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, P. R. of China   Fax: +86(931)7971989   Email: lizheng@nwnu.edu.cn
,
Rongzhi Li
College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, P. R. of China   Fax: +86(931)7971989   Email: lizheng@nwnu.edu.cn
,
Ben Ma
College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, P. R. of China   Fax: +86(931)7971989   Email: lizheng@nwnu.edu.cn
,
Jingya Yang
College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, P. R. of China   Fax: +86(931)7971989   Email: lizheng@nwnu.edu.cn
› Author Affiliations
Further Information

Publication History

Received: 15 July 2012

Accepted after revision: 07 August 2012

Publication Date:
10 September 2012 (online)


Abstract

A selective conjugate hydrocyanation of aromatic enones by a one-pot, two-step procedure using potassium hexacyanoferrate(II) as an original eco-friendly cyanide source, potassium hydroxide as a base, and benzoyl chloride as a promoter was described. This protocol has the advantages of a nontoxic cyanide source, high yield, and simple workup procedure.

Supporting Information

 
  • References and Notes

  • 2 Gerrits PG, Marcus J, Birikaki L, Gen A. Tetrahedron: Asymmetry 2001; 12: 971
    • 4a Dahuron N, Langlois N. Synlett 1996; 51
    • 4b Benedetti F, Berti F, Garau G, Martinuzzi I, Norbedo S. Eur. J. Org. Chem. 2003; 1973
  • 8 Li Z, Shi SY, Yang JY. Synlett 2006; 2495
  • 10 Saha D, Adak L, Mukherjee M, Ranu BC. Org. Biomol. Chem. 2012; 10: 952
  • 12 The analytical data for the isolated representative acyl cyanides are given below. Benzoyl Cyanide White solid. IR (KBr): 2224 (CN), 1679 (C=O) cm–1. 1H NMR (400 MHz, CDCl3): δ = 8.15–8.13 (m, 2 H), 7.82–7.78 (m, 1 H), 7.63–7.59 (m, 2 H). 13C NMR (100 MHz, CDCl3): δ = 167.8, 136.8, 133.2, 130.4, 129.5, 112.6.
  • 13 General Procedure The mixture of K4[Fe(CN)6] (0.4 mmol) and benzoyl chloride (2 mmol) was heated at 160 °C for 3 h, then the reaction system was cooled to 40 °C, and aromatic enone (1.5 mmol) in MeCN (5 mL) and KOH (2.4 mmol) in H2O (3 mL) were added. The mixture was further stirred at 40 °C for the appropriate time indicated in Table 4. After completion of the reaction, monitored by TLC, the resulting mixture was filtered to remove the solids, and the filtrate was concentrated and isolated by column chromatography using PE–EtOAc (10:1) as eluent to give the pure product. The analytical data for representative products are shown below. 4-Oxo-2,4-diphenylbutanenitrile (Table 4, Entry 1) White solid; mp 120–122 °C. IR (KBr): 1681 (C=O), 2238 (CN) cm–1. 1H NMR (400 MHz, CDCl3): δ = 3.51 (dd, 1 H, J = 5.6, 18.0 Hz, CHCH aHCO), 3.74 (dd, 1 H, J = 7.6, 18.0 Hz, CHCH bHCO), 4.58 (dd, J = 6.0, 6.4 Hz, 1 H, ArCHCH2), 7.26–7.43 (m, 7 H, ArH), 7.58–7.62 (m, 1 H, ArH), 7.92–7.94 (m, 2 H, ArH) ppm. 13C NMR (100 MHz, CDCl3): δ = 31.9, 44.5, 120.6, 127.5, 128.1, 128.4, 128.8, 129.3, 133.9, 135.2, 135.6 194.6 ppm. Anal. Calcd for C16H13NO (235.28): C, 81.68; H, 5.57; N, 5.95. Found: C, 81.59; H, 5.56; N, 5.97. 4-(4-Methoxyphenyl)-4-oxo-2-phenylbutanenitrile (Table 4, Entry 3) Oil. IR (KBr): 1676 (C=O), 2243 (CN) cm–1. 1H NMR (400 MHz, CDCl3): δ = 3.37 (dd, J = 6.0, 17.6 Hz, 1 H, CHCH aHCO), 3.60 (dd, J = 8.4, 17.6 Hz, 1 H, CHCH bHCO), 3.79 (s, 3 H, CH3), 4.49 (dd, J = 6.0, 8.0 Hz, 1 H, ArCHCH2), 6.85 (d, J = 6.8 Hz, 2 H, ArH), 7.23–7.37 (m, 5 H, ArH), 7.83 (d, J = 6.8 Hz, 2 H, ArH) ppm. 13C NMR (100 MHz, CDCl3): δ = 31.9, 44.1, 55.5, 113.9, 120.8, 127.4, 128.3, 128.7, 129.2, 130.4, 135.4, 164.0, 193.0 ppm. Anal. Calcd for C17H15NO2 (265.31): C, 76.96; H, 5.70; N, 5.28. Found: C, 76.80; H, 5.71; N, 5.30.