One-pot four-component synthesis of 2-aryl-3,3-dihaloacrylonitriles using potassium hexacyanoferrate(II) as environmentally benign cyanide source

ARTICLE

One-pot four-component synthesis of 2-aryl-3,3-dihaloacrylonitriles using potassium hexacyanoferrate(II) as environmentally benign cyanide source

Zhouxing Zhao; Zheng Li^*

Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu, 730070, P. R. China

ABSTRACT

An efficient route to one-pot four-component reactions of aroyl chlorides, potassium hexacyanoferrate(II), triphenylphosphine and carbon tetrahalides to synthesize 2-aryl-3,3-dichloroacrylonitriles and 2-aryl-3,3-dibromoacrylonitriles was described. This protocol has advantages of use of non-toxic cyanide source, high yield and simple work-up procedure.

Keywords: cyanation, four-component synthesis, potassium hexacyanoferrate(II), cyanide source, triphenylphosphine, 2-aryl-3,3-dichloroacrylonitriles, 2-aryl-3,3-dibromoacrylonitriles

RESUMO

Foi descrita uma rota eficiente para reações em uma etapa com quatro componentes incluindo cloretos de aroila, hexacianoferrato(II) de potássio, trifenilfosfina e tetrahaletos de carbono para sintetizar 2-aril-3,3-dicloroacrilonitrilas e 2-aril-3,3-dibromoacrilonitrilas. Este protocolo tem como vantagens o uso de uma fonte não-tóxica de cianeto, alto rendimento e procedimento experimental simples.

Introduction

3,3-Dichloroacrylonitriles and 3,3-dibromoacrylonitriles are well-known as the most important synthetic intermediates.¹ Although 2-aryl-3,3-dichloroacrylonitriles and 2-aryl-3,3-dibromoacrylonitriles could be prepared directly from phosphorus ylides with aroyl cyanides,² the commercially available aroyl cyanides are limited and comparatively expensive. Especially, synthesis of aroyl cyanides had to utilize strong toxic reagents as original cyanide sources, such as HgCN,³ NaCN,⁴ CuCN,⁵ KCN,⁶ and TMSCN,⁷ which render the cyanation of aroyl chlorides unsafe and environmentally unfriendly. In addition, the corresponding phosphorus ylides, which are unstable to oxygen and moisture, also required to synthesize by reactions of triphenylphosphine with carbon tetrahalides prior to use. Therefore, there is a need to explore environmentally benign cyanating agents and simple procedure for the synthesis of 2-aryl-3,3-dichloroacrylonitriles and 2-aryl-3,3-dibromoacrylonitriles.

Potassium hexacyanoferrate(II), K₄[Fe(CN)₆], is non-toxic and is even used in the food industry for metal precipitation. In addition, it has been described as an antiagglutinating auxiliary for table salt (NaCl). K₄[Fe(CN)₆] is commercially available on a ton scale and is even cheaper than KCN. Very recently, K₄[Fe(CN)₆] has been proved to be an efficient cyanide source for the cyanation of halogenated arenes and aroyl chlorides to prepare benzonitriles,⁸ and aroyl cyanides.⁹

Herein, we wish to report an efficient one-pot four-component synthesis of 2-aryl-3,3-dichloroacrylonitriles and 2-aryl-3,3-dibromoacrylonitriles using potassium hexacyanoferrate(II) as an environmentally benign cyanide source.

Results and Discussion

Initially, the reaction of benzoyl chloride, potassium hexacyanoferrate(II), triphenylphosphine and carbon tetrachloride was selected as a model reaction to examine the feasibility of one-pot four-component synthesis of 2-phenyl-3,3-dichloroacrylonitrile under different conditions (Scheme 1). It was found that the optimal mole ratio of benzoyl chloride to potassium hexacyanoferrate(II) and triphenylphosphine was 1:0.2:2 for the reaction, and the excess carbon tetrachloride were required because it acted both as a reactant and a solvent in this reaction. The 0.2 equivalent of potassium hexacyanoferrate(II) used in the reaction indicated that a small excess of CN^- was utilized in the reaction. The best yield was obtained by the procedure of first conducting the reaction of benzoyl chloride and potassium hexacyanoferrate(II) at 160 ºC for 3 h, then further reacting the resulting mixture with triphenylphosphine and carbon tetrachloride at 80 ºC for 2 h.

Under the optimal conditions, various substituted aroyl chlorides were examined for the one-pot four-component reactions. The results are summarized in Table 1. It was found that aroyl chlorides bearing electron-withdrawing substituents such as chloro, iodo and nitro groups on the aromatic ring gave the corresponding products in high yield (1b-1d, 1i, 1j and 1m). In contrast, aroyl chlorides bearing electron-donating substituents such as methyl, ethyl, methoxy and ethoxy groups on the aromatic ring gave the corresponding products in slightly lower yield under similar conditions (1e-1h, 1k and 1l). For ortho-substituted aroyl chlorides, the corresponding products were obtained in slightly lower yield than para-substituted ones, presumably due to the steric effect (1b, 1e and 1h). Heteroaroyl chloride, furoyl chloride, was also very efficient for the one-pot four-component reaction (1n).

In addition, one-pot four-component reactions of aroyl chlorides, potassium hexacyanoferrate(II), triphenylphosphine and carbon tetrabromide to synthesize various 2-aryl-3,3-dibromoacrylonitriles were also investigated (Scheme 2). In comparison with carbon tetrachloride, carbon tetrabromide is more active for the one-pot four-component reaction. Therefore milder conditions are required, such as lower reaction temperature and short reaction time although solvent is needed because carbon tetrabromide can not act as a solvent at low temperatures. The optimal conditions for the selected four-component reaction of benzoyl chloride, potassium hexacyanoferrate(II), triphenylphosphine and carbon tetrabromide were also investigated. It was found that the optimal mole ratio of benzoyl chloride to potassium hexacyanoferrate(II), triphenylphosphine and carbon tetrabromide was 1:0.2:2:1 for the reaction, and the best yield was obtained by the procedure of first conducting the reaction of benzoyl chloride and potassium hexacyanoferrate(II) at 160 ºC for 3 h, then further reacting the resulting mixture with triphenylphosphine and carbon tetrabromide in methylene chloride at 10 ºC for 0.5 h.

Under the optimal conditions, various substituted aroyl chlorides were examined for the reactions. The results are summarized in Table 2. The various substituted aroyl chlorides including electron-withdrawing groups and electron-donating groups are effective for the reactions, which have the similar effect on the yield to carbon tetrachloride. It is noteworthy to mention that 4-phenylbenzoyl chloride and isophthaloyl dichloride could also efficiently participate in the one-pot four-component reactions of carbon tetrabromide, but not for the reactions of carbon tetrachloride under the studied conditions (2l and 2m). Heteroaroyl chloride, furoyl chloride, was also very efficient for the one-pot four-component reaction to obtain 2-(furan-2-yl)-3,3-dibromoacrylonitrile (2n).

Conclusions

An efficient route to the one-pot four-component reactions of aroyl chlorides, potassium hexacyanoferrate(II), triphenylphosphine and carbon tetrahalides to synthesize 2-aryl-3,3-dichloroacrylonitriles and 2-aryl-3,3-dibromoacrylonitriles has been developed. The protocol has the advantages of using non-toxic potassium hexacyanoferrate(II) as an environmentally benign cyanide source instead of traditional strong toxic cyanating agents, high yield and simple work-up procedure.

Experimental

IR spectra were recorded using KBr pellets on an Alpha Centauri FTIR spectrophotometer and ¹H NMR and ¹³C NMR spectra on a Mercury-400BB instrument using CDCl₃ as solvent and Me₄Si as internal standard. Melting points were observed in an electrothermal melting point apparatus. Potassium hexacyanoferrate(II) dried at 80 ºC under vacuum for 24 h and finely powdered prior to use. All reactions were monitored by TLC. Flash column chromatography was carried out using 200-300 mesh silica gel at increased pressure.

General procedure for the preparation of 2-aryl-3,3-dichloroacrylonitriles

The mixture of aroyl chloride (10 mmol) and potassium hexacyanoferrate(II) (0.84 g, 2 mmol) was heated at 160 ºC for 3 h. After cooling to room temperature, triphenylphosphine (5.24 g, 20 mmol) and carbon tetrachloride (10 mL) were added. The resulting mixture was further stirred at 80 ºC for 2 h. Then the solid was removed by filtration, and the filtrate was evaporated to remove solvent under reduced pressure, and the residue was subjected to silica gel flash column chromatography (ethyl acetate, petroleum ether, 1:40, v/v) to obtain pure product. The analytical and spectral data for products are given below; melting poinst are given in Table 1.

2-Phenyl-3,3-dichloroacrylonitrile (1a)

Colorless oil; ¹H NMR (CDCl₃, 400 MHz): δ 7.52-7.41 (m, 5H, Ar-H); ¹³C NMR (CDCl₃, 100 MHz): δ 137.1, 130.6, 130.0, 128.8, 128.6, 115.5, 108.2; IR (KBr) ν_max/cm^-1: 3061, 2922, 2223, 1563, 1445, 930, 824, 759, 695. Found: C, 54.65; H, 2.53; N, 7.10. Calc. for C₉H₅Cl₂N: C, 54.58; H, 2.54; N, 7.07%.

2-(2-Chlorophenyl)-3,3-dichloroacrylonitrile (1b)

White solid; ¹H NMR (CDCl₃, 400 MHz): δ 7.60-7.31 (m, 4H, Ar-H), ¹³C NMR (CDCl₃, 100 MHz): δ 132.9, 132.4, 131.5, 130.4, 130.2, 127.4, 120.4, 115.6, 113.9; IR (KBr) ν_max/cm^-1: 3042, 2999, 2219, 1604, 1510, 1256, 927, 825. Found: C, 46.55; H, 1.72; N, 6.04. Calc. for C₉H₄Cl₃N: C, 46.49; H, 1.73; N, 6.02%.

2-(3-Chlorophenyl)-3,3-dichloroacrylonitrile (1c)

Light yellow solid; ¹H NMR (CDCl₃, 400 MHz): δ 7.52 (s, 1H, Ar-H), 7.44-7.39 (m, 3H, Ar-H); ¹³C NMR (CDCl₃, 100 MHz): δ 138.6, 134.9, 132.2, 130.3, 130.2, 128.8, 126.9, 115.1, 114.3; IR (KBr) ν_max/cm^-1: 3062, 2926, 2220, 1571, 1471, 1262, 943, 850. Found: C, 46.42; H, 1.73; N, 5.99. Calc. for C₉H₄Cl₃N: C, 46.49; H, 1.73; N, 6.02%.

2-(4-Chlorophenyl)-3,3-dichloroacrylonitrile (1d)

Light yellow solid; ¹H NMR (CDCl₃, 400 MHz): δ 7.48-7.40 (m, 4H, Ar-H); ¹³C NMR (CDCl₃, 100 MHz): δ 137.7, 136.2, 130.0, 129.1, 129.0, 115.2, 114.5; IR (KBr) ν_max/cm^-1: 3084, 2924, 2220, 1555, 1481, 1279, 927, 809. Found: C, 46.45; H, 1.72; N, 6.01. Calc. for C₉H₄Cl₃N: C, 46.49; H, 1.73; N, 6.02%.

2-(2-Methylphenyl)-3,3-dichloroacrylonitrile (1e)

Colorless oil; ¹H NMR (CDCl₃, 400 MHz): δ 7.22-7.00 (m, 4H, Ar-H), 2.16 (s, 3H, CH₃); ¹³C NMR (CDCl₃, 100 MHz): δ 138.5, 136.1, 130.4, 130.0, 129.9, 128.7, 126.2, 114.7, 114.2, 18.8; IR (KBr) ν_max/cm^-1: 3067, 2925, 2219, 1571, 1485, 1258, 930, 753. Found: C, 56.53; H, 3.32; N, 6.62. Calc. for C₁₀H₇Cl₂N: C, 56.63; H, 3.33; N, 6.60%.

2-(3-Methylphenyl)-3,3-dichloroacrylonitrile (1f)

Colorless oil; ¹H NMR (CDCl₃, 400 MHz): δ 7.28-7.20 (m, 4H, Ar-H), 2.35 (s, 3H, CH₃); ¹³C NMR (CDCl₃, 100 MHz): δ 138.5, 136.6, 130.6, 130.4, 128.9, 128.5, 125.5, 115.5, 115.4, 21.0; IR (KBr) ν_max/cm^-1: 3039, 2923, 2222, 1565, 1485, 1267, 931, 877, 791, 697. Found: C, 56.56; H, 3.34; N, 6.56. Calc. for C₁₀H₇Cl₂N: C, 56.63; H, 3.33; N, 6.60%.

2-(4-Methylphenyl)-3,3-dichloroacrylonitrile (1g)

Colorless oil; ¹H NMR (CDCl₃, 400 MHz): δ 7.37 (d, 2H, J 8.4 Hz, Ar-H), 7.19 (d, 2H, J 8.4 Hz, Ar-H), 2.32 (s, 3H, CH₃); ¹³C NMR (CDCl₃, 100 MHz): δ 140.0, 135.7, 129.2, 128.2, 127.4, 115.3, 115.2, 20.9; IR (KBr) ν_max/cm^-1: 3031, 2923, 2222, 1573, 1509, 1258, 929, 815, 771. Found: C, 56.70; H, 3.32; N, 6.57. Calc. for C₁₀H₇Cl₂N: C, 56.63; H, 3.33; N, 6.60%.

2-(2-Ethylphenyl)-3,3-dichloroacrylonitrile (1h)

Colorless oil; ¹H NMR (CDCl₃, 400 MHz): δ 7.25-6.97 (m, 4H, Ar-H), 2.88 (q, 2H, J 6.4 Hz, CH₂), 1.26 (t, 3H, J 6.4 Hz, CH₃); ¹³C NMR (CDCl₃, 100 MHz): δ 143.1, 129.1, 129.0, 128.8, 124.7, 124.1, 121.6, 120.3, 119.2, 25.6, 14.3; IR (KBr) ν_max/cm^-1: 3032, 2918, 2224, 1589, 1497, 1234, 942, 842. Found: C, 58.50; H, 3.99; N, 6.20. Calc. for C₁₁H₉Cl₂N: C, 58.43; H, 4.01; N, 6.19%.

2-(3-Nitrophenyl)-3,3-dichloroacrylonitrile (1i)

White solid; ¹H NMR (CDCl₃, 400 MHz): δ 8.45 (s, 1H, Ar-H), 8.33 (d, 1H, J 8.0 Hz, Ar-H), 7.87 (d, 1H, J 8.0 Hz, Ar-H), 7.70 (t, 1H, J 8.0 Hz, Ar-H); ¹³C NMR (CDCl₃, 100 MHz): δ 148.2, 140.1, 134.6, 132.2, 130.2, 124.9, 123.9, 114.7, 113.4; IR (KBr) ν_max/cm^-1: 3081, 2924, 2223, 1614, 1532, 1348, 1263, 947. Found: C, 44.55; H, 1.67; N, 11.57. Calc. for C₉H₄Cl₂N₂ O₂: C, 44.48; H, 1.66; N, 11.53%.

2-(4-Nitrophenyl)-3,3-dichloroacrylonitrile (1j)

White solid; ¹H NMR (CDCl₃, 400 MHz): δ 8.33 (d, J 9.2 Hz, 2H, Ar-H), 7.74 (d, 2H, J 9.2 Hz, Ar-H); ¹³C NMR (CDCl₃, 100 MHz): δ 148.3, 140.2, 136.7, 130.0, 124.1, 114.7, 113.8; IR (KBr) ν_max/cm^-1: 3049, 2923, 2235, 1555, 1481, 1377, 1226, 1024, 939, 748. Found: C, 44.45; H, 1.66; N, 11.49. Calc. for C₉H₄Cl₂N₂ O₂: C, 44.48; H, 1.66; N, 11.53%.

2-(4-Ethoxyphenyl)-3,3-dichloroacrylonitrile (1k)

White solid; ¹H NMR (CDCl₃, 400 MHz): δ 7.46 (d, 2H, J 8.8 Hz, Ar-H), 6.93 (d, 2H, J 8.8 Hz, Ar-H), 4.06 (q, 2H, J 6.8 Hz, CH₂), 1.43 (t, 3H, J 6.8 Hz, CH₃); ¹³C NMR (CDCl₃, 100 MHz): δ 160.0, 135.3, 130.2, 122.6, 115.8, 115.2, 114.6, 63.6, 14.6; IR (KBr) ν_max/cm^-1: 3059, 2988, 2218, 1606, 1510, 1265, 924. Found: C, 54.50; H, 3.77; N, 5.80. Calc. for C₁₁H₉Cl₂NO: C, 54.57; H, 3.75; N, 5.79%.

2-(4-Methoxyphenyl)-3,3-dichloroacrylonitrile (1l)

White solid; ¹H NMR (CDCl₃, 400 MHz): δ 7.48 (d, 2H, J 9.2 Hz, Ar-H), 6.95 (d, 2H, J 9.2 Hz, Ar-H), 3.84 (s, 3H, CH₃); ¹³C NMR (CDCl₃, 100 MHz): δ 160.7, 135.4, 130.2, 122.8, 115.7, 115.2, 114.2, 55.3; IR (KBr) ν_max/cm^-1: 3067, 2988, 2218, 1589, 1465, 1287, 854, 765. Found: C, 52.59; H, 3.07; N, 6.17. Calc. for C₁₀H₇Cl₂NO: C, 52.66; H, 3.09; N, 6.14%.

2-(4-Iodophenyl)-3,3-dichloroacrylonitrile (1m)

White solid; ¹H NMR (CDCl₃, 400 MHz): δ 7.79 (d, 2H, J 8.8 Hz, Ar-H), 7.26 (d, 2H, J 8.8 Hz, Ar-H); ¹³C NMR (CDCl₃, 100 MHz): δ 138.1, 137.8, 130.3, 130.1, 115.2, 114.7, 96.6; IR (KBr) ν_max/cm^-1: 3065, 2220, 1572, 1481, 1288, 1276, 933, 834. Found: C, 33.41; H, 1.23; N, 4.31. Calc. for C₉H₄Cl₂IN: C, 33.37; H, 1.24; N, 4.32%.

2-(Furan-2-yl)-3,3-dichloroacrylonitrile (1n)

White solid; ¹H NMR (CDCl₃, 400 MHz): δ 7.76 (d, 1H, J 1.6 Hz, Fu-H), 7.04 (d, 1H, J 4.4 Hz, Fu-H), 6.41 (dd, 1H, J 3.6 Hz, J 1.6 Hz, Fu-H), ¹³C NMR (CDCl₃, 100 MHz): δ 148.3, 140.2, 136.6, 130.0, 124.1, 114.7, 113.8; IR (KBr) ν_max/cm^-1: 3109, 2923, 2220, 1520, 1350, 931, 858, 817, 698. Found: C, 44.66; H, 1.62; N, 7.43. Calc. for C₇H₃Cl₂NO: C, 44.72; H, 1.61; N, 7.45%.

General procedure for the preparation of 2-aryl-3,3-dibromoacrylonitriles

The mixture of aroyl chloride (10 mmol) and potassium hexacyanoferrate(II) (0.84 g, 2 mmol) was heated at 160 ºC for 3 h. After cooling to 10 ºC, triphenylphosphine (5.24 g, 20 mmol) and carbon tetrabromide (3.31 g, 10 mmol) in 10 mL of methylene chloride was slowly added dropwise with stirring. The resulting mixture was further stirred at 10 ºC for 0.5 h. Then the solid was removed by filtration, and the filtrate was evaporated to remove solvent under reduced pressure, and the residue was subjected to silica gel flash column chromatography (ethyl acetate, petroleum ether, 1:40, v/v) to obtain pure product. The analytical and spectral data for products are given below; melting points are given in Table 2.

2-Phenyl-3,3-dibromoacrylonitrile (2a)

White solid; ¹H NMR (CDCl₃, 400 MHz): δ 7.48-7.45 (m, 5H, Ar-H); ¹³C NMR (CDCl₃, 100 MHz): δ 133.3, 130.0, 128.9, 128.5, 122.6, 117.0, 109.7; IR (KBr) ν_max/cm^-1: 3062, 2923, 2216, 1443, 842. Found: C, 37.71; H, 1.77; N, 4.86. Calc. for C₉H₅Br₂N: C, 37.67; H, 1.76; N, 4.88%.

2-(2-Chlorophenyl)-3,3-dibromoacrylonitrile (2b)

White solid; ¹H NMR (CDCl₃, 400 MHz): δ 7.50-7.31 (m, 4H, Ar-H); ¹³C NMR (CDCl₃, 100 MHz): δ 132.8, 132.4, 131.5, 130.4, 130.2, 127.4, 120.3, 115.5, 113.9; IR (KBr) ν_max/cm^-1: 3069, 2924, 2218, 1554, 1467, 11435, 1287,1038, 853, 750. Found: C, 33.69; H, 1.25; N, 4.34. Calc. for C₉H₄Br₂ClN: C, 33.63; H, 1.25; N, 4.36%.

2-(3-Chlorophenyl)-3,3-dibromoacrylonitrile (2c)

White solid; ¹H NMR (CDCl₃, 400 MHz): δ 7.48-7.35 (m, 4H, Ar-H); ¹³C NMR (CDCl₃, 100 MHz): δ 134.9, 134.7, 130.3, 130.2, 128.6, 126.7, 121.2, 116.6, 111.1; IR (KBr) ν_max/cm^-1: 3065, 2927, 2218, 1589, 1434, 1282, 981, 848, 751. Found: C, 33.59; H, 1.26; N, 4.35. Calc. for C₉H₄Br₂ClN: C, 33.63; H, 1.25; N, 4.36%.

2-(4-Chlorophenyl)-3,3-dibromoacrylonitrile (2d)

White solid; ¹H NMR (CDCl₃, 400 MHz): δ 7.43 (s, 4H, Ar-H); ¹³C NMR (CDCl₃, 100 MHz): δ 136.2, 131.6, 129.9, 129.2, 121.5, 116.7, 110.4; IR (KBr) ν_max/cm^-1: 2922, 2213, 1590, 1482, 1095, 831. Found: C, 33.65; H, 1.25; N, 4.38. Calc. for C₉H₄Br₂ClN: C, 33.63; H, 1.25; N, 4.36%.

2-(2-Methylphenyl)-3,3-dibromoacrylonitrile (2e)

White solid; ¹H NMR (CDCl₃, 400 MHz): δ 7.37-7.18 (m, 4H, Ar-H), 2.33 (s, 3H, CH₃); ¹³C NMR (CDCl₃, 100 MHz): δ 136.1, 133.3, 130.8, 130.2, 128.8, 126.6, 122.4, 116.1, 111.9, 19.3; IR (KBr) ν_max/cm^-1: 3062, 2920, 2214, 1546, 1453, 1251, 852, 735. Found: C, 39.86; H, 2.35; N, 4.63. Calc. for C₁₀H₇Br₂N: C, 39.91; H, 2.34; N, 4.65%.

2-(3-Methylphenyl)-3,3-dibromoacrylonitrile (2f)

White solid; ¹H NMR (CDCl₃, 400 MHz): δ 7.34-7.24 (m, 4H, Ar-H), 2.39 (s, 3H, CH₃); ¹³C NMR (CDCl₃, 100 MHz): δ 138.8, 133.2, 130.8, 128.9, 128.8, 125.6, 122.7, 117.1, 109.4, 21.3; IR (KBr) ν_max/cm^-1: 3018, 2921, 2214, 1600, 1554, 1095, 850, 789. Found: C, 39.95; H, 2.34; N, 4.67. Calc. for C₁₀H₇Br₂N: C, 39.91; H, 2.34; N, 4.65%.

2-(4-Methylphenyl)-3,3-dibromoacrylonitrile (2g)

White solid; ¹H NMR (CDCl₃, 400 MHz): δ 7.39-7.23 (m, 4H, Ar-H), 2.38 (s, 3H, CH₃); ¹³C NMR (CDCl₃, 100 MHz): δ 140.4, 130.4, 129.6, 128.4, 122.6, 117.1, 108.9, 21.4; IR (KBr) ν_max/cm^-1: 3028, 2917, 2220, 1613, 1551, 1505, 1260, 849, 823. Found: C, 39.96; H, 2.35; N, 4.66. Calc. for C₁₀H₇Br₂N: C, 39.91; H, 2.34; N, 4.65%.

2-(4-Nitrophenyl)-3,3-dibromoacrylonitrile (2h)

White solid; ¹H NMR (CDCl₃, 400 MHz): δ 8.32 (d, 2H, J 7.2 Hz, Ar-H), 7.71 (d, 2H, J 7.2 Hz, Ar-H); ¹³C NMR (CDCl₃, 100 MHz): δ 148.3, 139.1, 129.9, 124.2, 120.6, 116.2, 112.7; IR (KBr) ν_max/cm^-1: 3104, 2924, 2216, 1600, 1518, 1350, 1294, 858. Found: C, 32.49; H, 1.21; N, 8.41. Calc. for C₉H₄Br₂N₂ O₂: C, 32.56; H, 1.21; N, 8.44%.

2-(3,5-Dinitrophenyl)-3,3-dibromoacrylonitrile (2i)

White solid; ¹H NMR (CDCl₃, 400 MHz): δ 9.13 (s, 1H, Ar-H), 8.74 (s, 2H, Ar-H); ¹³C NMR (CDCl₃, 100MHz): δ 148.7, 136.3, 129.0, 128.9, 120.0, 118.4, 115.6; IR (KBr) ν_max/cm^-1: 3094, 2983, 2224, 1627, 1543, 1344, 1279, 918, 853, 729. Found: C, 28.73; H, 0.80; N, 11.11. Calc. for C₉H₃Br₂N₃ O₄: C, 28.68; H, 0.80; N, 11.15%.

2-(3-Nitrophenyl)-3,3-dibromoacrylonitrile (2j)

White solid; ¹H NMR (CDCl₃, 400 MHz): δ 8.41 (s, 1H, Ar-H), 8.33 (d, 1H, J 8.4 Hz, Ar-H), 7.84 (d, 1H, J 8.4 Hz, Ar-H), 7.69 (t, 1H, J 8.4 Hz, Ar-H); ¹³C NMR (CDCl₃, 100 MHz): δ 148.3, 134.7, 134.5, 130.3, 124.8, 123.8, 120.3, 116.2, 112.8; IR (KBr) ν_max/cm^-1: 3104, 2924, 2216, 1600, 1518, 1350, 1294, 858. Found: C, 32.61; H, 1.20; N, 8.46. Calc. for C₉H₄Br₂N₂ O₂: C, 32.56; H, 1.21; N, 8.44%.

2-(4-Methoxyphenyl)-3,3-dibromoacrylonitrile (2k)

IR ¹H NMR (CDCl₃, 400 MHz): δ 7.44 (d, 2H, J 9.2 Hz, Ar-H), 6.94 (d, 2H, J 9.2 Hz, Ar-H), 3.84 (s, 3H, CH₃). ¹³C NMR (CDCl₃, 100 MHz): δ 160.6, 130.1, 125.4, 122.2, 117.1, 114.2, 108.0, 55.3. (KBr) ν_max/cm^-1: 2999, 2939, 2214, 1605, 1508, 1259, 1182, 1021, 829. Found: C, 37.95; H, 2.22; N, 4.41. Calc. for C₁₀H₇Br₂NO: C, 37.89; H, 2.23; N, 4.42%.

2-(4-Biphenyl)-3,3-dibromoacrylonitrile (2l)

Brown solid; ¹H NMR (CDCl₃, 400 MHz): δ 7.74-7.42 (m, 9H, Ar-H); ¹³C NMR (CDCl₃, 100 MHz): δ 145.6, 139.1, 132.5, 129.0, 128.6, 127.9, 127.7, 127.2, 122.1, 118.9, 110.8; IR (KBr) ν_max/cm^-1: 3063, 2922, 2223, 1600, 1479, 1400, 842, 767. Found: C, 49.69; H, 2.49; N, 3.87. Calc. for C₁₅H₉Br₂N: C, 49.62; H, 2.50; N, 3.86%.

1,3-bis(2,2-dibromo-1-cyanovinyl)benzene (2m)

White solid; ¹H NMR (CDCl₃, 400 MHz): δ 7.75-7.42 (m, 4H, Ar-H); ¹³C NMR (CDCl₃, 100 MHz): δ 133.3, 132.4, 132.3, 132.2, 131.5, 128.5, 128.4; IR (KBr) ν_max/cm^-1: 3055, 2923, 2200, 1636, 1479, 1433, 1102, 713, 514. Found: C, 29.14; H, 0.81; N, 5.63. Calc. for C₁₂H₄Br₄N₂ : C, 29.07; H, 0.81; N, 5.65%.

2-(Furan-2-yl)-3,3-dibromoacrylonitrile (2n)

White solid; ¹H NMR (CDCl₃, 400 MHz): δ 7.58 (d, 1H, J 1.6 Hz, Fu-H), 7.08 (d, 1H, J 4.0 Hz, Fu-H), 6.54 (dd, 1H, J 3.6 Hz, J 1.6 Hz, Fu-H), ¹³C NMR (CDCl₃, 100 MHz): δ 145.9, 144.2, 115.3, 114.5, 113.5, 112.1, 103.7. IR (KBr) ν_max/cm^-1: 3153, 2227, 1476, 1030, 850, 750. Found: C, 30.29; H, 1.08; N, 5.08. Calc. for C₇H₃Br₂NO: C, 30.36; H, 1.09; N, 5.06%.

Supplementary Information

Full set of IR, ¹H NMR and ¹³C NMR spectra are available free of charge at http://jbcs.sbq.org.br, as pdf file.

Acknowledgments

The authors thank the National Natural Science Foundation of China (20772096), and Key Laboratory of Eco-Environment-Related Polymer Materials (Northwest Normal University), Ministry of Education of China for the financial support of this work.

References

1. Shablykin, O. V.; Gakh, A. A.; Brovarets, V. S.; Rusanov, E. B.; Drach, B. S.; Heteroat. Chem. 2008, 9, 506; Shablykin, O. V.; Brovarets, V. S.; Drach, B. S.; Russ. J. Gen. Chem. 2007, 77, 1308; Brovarets, V. S.; Pilyo, S. G.; Chernega, A. N.; Romanenko, E. A.; Drach, B. S.; Russ. J. Gen. Chem. 1999, 69, 1577; Popil'nichenko, S. V.; Brovarets, V. S.; Chernega, A. N.; Poltorak, D. V.; Drach, B. S.;Heteroat. Chem. 2006, 17, 411; Golovchenko, O. V.; Pilyo, S. G.; Brovarets, V. S.; Chernega, A. N.; Drach, B. S.; Heteroat. Chem. 2004, 15, 454; Pilyo, S. G.; Brovarets, V. S.; Vinogradova, T. K.; Golovchenko, A. V.; Drach, B. S.; Russ. J. Gen. Chem. 2002, 72, 1714; Kozachenko, A. P.; Shablykin, O. V.; Vasilenko, A. N.; Brovarets, V. S.; Russ. J. Gen. Chem. 2010, 80, 127; Kozachenko, A. P.; Shablykin, O. V.; Rusanov, E. B.; Vasilenko, A. N.; Brovarets, V. S.; Russ. J. Gen. Chem. 2009, 79, 996.

2. Soulen, R. L.; Carlson, S. C.; Lang, F.; J. Org. Chem. 1973, 38, 479; Clement, B. A.; Soulen, R. L.; J. Org. Chem. 1974, 39, 97; Clement, B. A.; Soulen, R. L.; J. Org. Chem. 1976, 41, 556; Sepiol, J. J.; Sepiol, J. A.; Soulen, R. L.; J. Org. Chem. 1984, 49, 1125.

3. Haase, K.; Hoffmann, H. M.; Angew. Chem., Int. Ed. 1982, 21, 83.

4. Kazuaki, S.; Bull. Chem. Soc. Jpn. 1987, 60, 1085.

5. Oakwood, T. S.; Weisgerber, C. A.; Org. Synth. 1955, 24, 14.

6. Patricinio, A. F.; Moran, P. J. S.; J. Braz. Chem. Soc. 2001, 12, 7; Cao, Y. Q.; Du, Y. F.; Chen, B. H.; Li, J. T.; Synth. Commum. 2004, 34, 2951.

7. Harle, H.; Jochims, J. C.; Chem. Ber. 1986, 119, 1400; Zeng, W.; Yang, J.; Meng, B.; Zhang, B.; Jiang, M.; Chen, F. X.; Lett. Org. Chem. 2009, 6, 637.

8. Schareina, T.; Zapf, A.; Beller, M.; J. Organomet. Chem. 2004, 689, 4576; Schareina, T.; Zapf, A.; Beller, M.; Chem. Commun. 2004, 1388; Schareina, T.; Zapf, A.; Beller, M.; Tetrahedron Lett. 2005, 46, 2585; Schareina, T.; Zapf, A.; Magerlein, W.; Muller, N.; Beller, M.; Tetrahedron Lett. 2007, 48, 1087; Weissman, S. A.; Zewge, D.; Chen, C.; J. Org. Chem. 2005, 70, 1508; Grossman, O.; Gelman, D.; Org. Lett. 2006, 8, 1189; Li, L. H.; Pan, Z. L.; Duan, X. H.; Liang, Y. M.; Synlett 2006, 2094; Velmathi, S.; Leadbeater, N. E.; Tetrahedron Lett. 2008, 49, 4693; Chen, G.; Weng, J.; Zheng, Z.; Zhu, X.; Cai, Y.; Cai, J.; Wan, Y.; Eur. J. Org. Chem. 2008, 3524; Cheng, Y. N.; Duan, Z.; Yu, L. J.; Li, Z. X.; Zhu, Y.; Wu, Y. J.; Org. Lett. 2008, 10, 901; Franz, A. W.; Popa, L. N.; Muller, T. J. J.; Tetrahedron Lett. 2008, 49, 3300; Ren, Y. L.; Liu, Z. F.; He, S. B.; Zhao, S.; Wang, J. J.; Niu, R. Q.; Yin, W. P.; Org. Process Res. Dev. 2009, 13, 764.

9. Li, Z.; Shi, S. Y.; Yang, J. Y.; Synlett 2006, 2495.

Submitted: April 27, 2010

Published online: September 8, 2010

Supplementary Information

Figure S1 - Click to the enlarge

Figure S2 - Click to the enlarge

Figure S3 - Click to the enlarge

Figure S4 - Click to the enlarge

Figure S5 - Click to the enlarge

Figure S6 - Click to the enlarge

Figure S7 - Click to the enlarge

Figure S8 - Click to the enlarge

Figure S9 - Click to the enlarge

Figure S10 - Click to the enlarge

Figure S11 - Click to the enlarge

Figure S12 - Click to the enlarge

Figure S13 - Click to the enlarge

Figure S14- Click to the enlarge

Figure S14 - Click to the enlarge

Figure S16 - Click to the enlarge

Figure S17 - Click to the enlarge

Figure S18 - Click to the enlarge

Figure S19 - Click to the enlarge

Figure S20 - Click to the enlarge

Figure S21 - Click to the enlarge

Figure S22 - Click to the enlarge

Figure S23 - Click to the enlarge

Figure S24 - Click to the enlarge

Figure S25 - Click to the enlarge

Figure S26 - Click to the enlarge

Figure S27 - Click to the enlarge

Figure S28 - Click to the enlarge

Figure S29 - Click to the enlarge

Figure S30- Click to the enlarge

Figure S31 - Click to the enlarge

Figure S32 - Click to the enlarge

Figure S33- Click to the enlarge

Figure S34 - Click to the enlarge

Figure S35 - Click to the enlarge

Figure S36 - Click to the enlarge

Figure S37 - Click to the enlarge

Figure S38 - Click to the enlarge

Figure S39 - Click to the enlarge

Figure S40 - Click to the enlarge

Figure S41 - Click to the enlarge

Figure S42 - Click to the enlarge

Figure S43 - Click to the enlarge

Figure S44 - Click to the enlarge

Figure S45 - Click to the enlarge

Figure S46 - Click to the enlarge

Figure S47 - Click to the enlarge

Figure S48 - Click to the enlarge

Figure S49 - Click to the enlarge

Figure S50 - Click to the enlarge

Figure S51 - Click to the enlarge

Figure S52 - Click to the enlarge

Figure S53 - Click to the enlarge

Figure S54 - Click to the enlarge

Figure S55 - Click to the enlarge

Figure S56 - Click to the enlarge

Figure S57 - Click to the enlarge

Figure S58 - Click to the enlarge

Figure S59 - Click to the enlarge

Figure S60 - Click to the enlarge

Figure S61 - Click to the enlarge

Figure S62 - Click to the enlarge

Figure S63 - Click to the enlarge

Figure S64 - Click to the enlarge

Figure S65 - Click to the enlarge

Figure S66 - Click to the enlarge

Figure S67 - Click to the enlarge

Figure S68 - Click to the enlarge

Figure S69 - Click to the enlarge

Figure S70 - Click to the enlarge

Figure S71 - Click to the enlarge

Figure S72 - Click to the enlarge

Figure S73 - Click to the enlarge

Figure S74 - Click to the enlarge

Figure S75 - Click to the enlarge

Figure S76 - Click to the enlarge

Figure S77 - Click to the enlarge

Figure S78 - Click to the enlarge

Figure S79 - Click to the enlarge

Figure S80 - Click to the enlarge

Figure S81 - Click to the enlarge

Figure S82 - Click to the enlarge

Figure S83 - Click to the enlarge

Figure S84 - Click to the enlarge

Publication Dates

• Publication in this collection
  31 Jan 2011
• Date of issue
  Jan 2011

History

• Reviewed
  08 Sept 2010
• Received
  27 Apr 2010