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Supporting Information for

Poly(ethylene glycol)-functionalized imidazolium

salts–palladium-catalyzed Suzuki reaction in water

Ning Liu, Chun Liu,* and Zilin Jin

State Key Laboratory of Fine Chemicals, Dalian University of Technology, Linggong Road 2,

Dalian 116024, China

E-Mail: [email protected]

Contents

Materials and Methods and Experimental Procedure S1-S3

Characterization Data S4-S5

References S6

NMR and MS Spectra for Imidazolium Salts S7-S11

1H NMR Spectra for Cross-Coupling Products S12-S16

Materials and Methods

Aryl halides and arylboronic acids were purchased from Alfa Aesar. Other chemicals were obtained commercially and used without any prior purification. NMR spectra were recorded on a Brucker Advance II 400 spectrometer using TMS as internal standard (400 MHz for 1H NMR and 100 MHz for 13C NMR). Mass spectroscopy data (ESI-MS) of the compounds were collected on a UPLC/Q-TOF mass spectrometer. All products were isolated by short chromatography on a silica gel (200-300 mesh) column using petroleum ether (60-90 C), unless otherwise noted. Compounds described in the literature were characterized by 1H NMR spectra compared to reported data.

Synthesis of MeOPEG550OSO2CH3

A solution of methanesulfonyl chloride (4.6 g 0.04 mol) in dry toluene (50 mL) was added dropwise to a mixture of MeOPEG550OH (22 g, 0.04 mol), Et3N (4.1 g, 0.04 mol) in dry toluene (100 mL) under N2. The mixture was stirred at 0 C for 24 h and

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then the white solid by-product was removed by filtration. The filtrate was evaporated in vacuum to afford MeOPEG550OSO2CH3 (22.9 g, yield 89%) a colorless liquid. 1H NMR (400 MHz, CDCl3, TMS): δ 4.39-4.36 (m, 2H, CH2OSO2), 3.78-3.53 (m, 49H, PEG-H), 3.37 (s, 3H, PEG-OCH3), 3.09 (s, 3H, OSO2CH3) ppm.

Synthesis of imidazolium salts 1, 2, and 3

A mixture of MeOPEG550OSO2CH3 (1.6 g, 2.5 mmol) and the respective substituted imidazole (3.0 mmol) was heated in a sealed tube at 100 °C for 24 h. The resulting solution was isolated by short chromatography on a silica gel (200–300 mesh) column using CH2Cl2 and CH3OH. Imidazolium salt 1. Yield: 1.57 g, 87%, a yellow liquid. 1H NMR (400 MHz, CDCl3, TMS): δ 9.76 (s, 1H, CHimid), 7.68 (s, 1H, CHimid), 7.41 (s, 1H, CHimid), 4.52 (t, J = 4.0 Hz, 2H, NCH2), 4.01 (s, 3H, NCH3), 3.88-3.54 (m, 52H, PEG-H), 3.38 (s, 3H, PEG-OCH3), 2.79 (s, 3H, OSO2CH3) ppm. 13C NMR δ 137.95 (Cimid), 123.55 (Cimid), 122.92 (Cimid), 71.86-69.06 (CPEG), 58.96 (OCH3), 49.51 (CH2), 39.53 (OSO2CH3), 36.24 (NCH3) ppm; MS (ESI) m/z [M]+: 449.2745, 493.2917, 537.3089, 581.3403, 625.3712, 669.3821, 713.4109, 757.4518, 801.4578, 845.5190, 889.5416. Imidazolium salt 2. Yield: 1.22 g, 65%, a pale yellow liquid. 1H NMR (400 MHz, CDCl3, TMS): δ 9.86 (s, 1H, CHimid), 7.69 (s, 1H, CHimid), 7.42 (s, 1H, CHimid), 4.55 (t, J = 4.4 Hz, 2H, NCH2), 4.24 (t, J = 8.0 Hz, 2H, NCH2), 3.89-3.54 (m, 49H, PEG-H), 3.38 (s, 3H, PEG-OCH3), 2.77 (s, 3H, OSO2CH3), 1.95 (sextet, J = 8.0 Hz, 2H, CH2 ), 0.99 (t, J = 8.0 Hz, 3H, CH3) ppm. 13C NMR δ 137.66 (Cimid), 123.67 (Cimid), 121.31 (Cimid), 71.87-69.17 (CPEG), 58.97 (OCH3), 51.27 (NCH2), 49.51 (NCH2), 39.55 (OSO2CH3), 23.49 (CH2), 10.71 (CH3) ppm; MS (ESI) m/z [M]+: 433.1993, 477.2220, 521.2362, 565.2465, 609.2604, 653.2875, 697.3015, 741.3147, 785.3329, 829.3502, 873.3594, 917.3660. Imidazolium salt 3. Yield: 1.69 g, 88%, a pale yellow liquid. 1H NMR (400 MHz, CDCl3, TMS): δ 10.13 (s, 1H, CHimid), 7.64 (s, 1H, CHimid), 7.25 (s, 1H, CHimid), 4.75 (heptet, J = 8.0 Hz, 1H, NCH), 4.60 (t, J = 4.4 Hz, 2H, NCH2), 3.90-3.53 (m, 47H, PEG-H), 3.38 (s, 3H, PEG-OCH3), 2.80 (s, 3H, OSO2CH3), 1.61 (d, J = 8.0 Hz, 6H, 2CH3) ppm. 13C NMR δ 136.51 (Cimid), 123.79 (Cimid), 118.99 (Cimid), 71.86-69.21 (CPEG), 58.96 (OCH3), 53.03 (NCH), 49.54 (NCH2), 39.51 (OSO2CH3), 22.95 (2CH3) ppm; MS (ESI) m/z [M]+: 345.2864, 389.3203, 433.3504, 477.3857, 521.4127, 565.4488, 609.4761, 653.5029, 697.5443, 741.5858, 785.6030, 829.6337, 873.6565, 917.7091, 961.7439.

General Procedure for Suzuki Reaction

All Suzuki reactions were carried out without an inert atmosphere. A mixture of aryl halide (0.5 mmol), arylboronic acid (0.75 mmol), Et3N (1 mmol, 101 mg), 0.56


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mg Pd(OA)2 (0.0025 mmol), and imidazolium salts (7.2 mg, 0.01 mmol) in H2O (1 ml) was allowed to react in a sealed tube at 100 C. The activation of aryl chlorides required the addition of TBAB (0.75 mmol) as a phase transfer catalyst. The reaction mixtures was added to brine (15 mL) and extracted three times with ethyl acetate (3×15 mL). The solvent was concentrated under vacuum and the product was isolated by short chromatography on a silica gel (200–300 mesh) column.


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Characterization Data of Products

4-methoxy-1,1'-biphenyl1

1H NMR (400 MHz, CDCl3): δ 7.56-7.51 (m, 4H, Ar-H), 7.41 (t, J = 8.0 Hz, 2H, Ar-H), 7.32-7.28 (m, 1H, Ar-H), 7.00-6.96 (m, 2H, Ar-H), 3.85 (s, 3H, OCH3), ppm.

[1,1'-biphenyl]-4-carbonitrile2

1H NMR (400 MHz, CDCl3): δ 7.73 (d, J = 8.4 Hz, 2H, Ar-H), 7.68 (d, J = 8.0 Hz, 2H, Ar-H), 7.59 (d, J = 7.2 Hz, 2H, Ar-H), 7.48 (t, J = 7.2Hz, 2H, Ar-H), 7.42 (t, J = 7.2 Hz, 1H, Ar-H), ppm.

4-acetyl-1,1'-biphenyl3

1H NMR (400 MHz, CDCl3): δ 8.03 (d, J = 8.0 Hz, 2H, Ar-H), 7.68 (d, J = 8.0 Hz, 2H, Ar-H), 7.63 (d, J = 7.2 Hz, 2H, Ar-H), 7.47 (t, J = 7.2 Hz, 2H, Ar-H), 7.40 (t, J = 7.2 Hz, 1H, Ar-H), 2.64 (s, 3H, O=CCH3), ppm.

4-nitro-1,1'-biphenyl1

1H NMR (400 MHz, CDCl3): δ 8.30 (d, J = 8.8 Hz, 2H, Ar-H), 7.74 (d, J = 8.8 Hz, 2H, Ar-H), 7.63 (d, J = 8.4 Hz, 2H, Ar-H), 7.52-7.43 (m, 3H, Ar-H), ppm.

4-methoxy-[1,1'-biphenyl]-4'-carbonitrile4

1H NMR (400 MHz, CDCl3): δ 7.70 (d, J = 8.4 Hz, 2H, Ar-H), 7.66 (d, J = 8.4 Hz, 2H, Ar-H), 7.49 (d, J = 8.0 Hz, 2H, Ar-H), 7.29 (d, J = 8.0 Hz, 2H, Ar-H), 2.41 (s, 3H, CH3), ppm.

4'-methyl-[1,1'-biphenyl]-2-carbonitrile4

1H NMR (400 MHz, CDCl3): δ 7.74 (d, J = 7.6 Hz, 1H, Ar-H), 7.62 (t, J = 7.6 Hz, 1H, Ar-H), 7.50 (d, J = 8.0 Hz, 1H, Ar-H), 7.46 (d, J = 8.0 Hz, 2H, Ar-H), 7.41 (t, J = 7.6


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Hz, 1H, Ar-H), 7.30 (d, J = 7.6 Hz, 2H, Ar-H), 2.42 (s, 3H, CH3), ppm.

4'-methyl-[1,1'-biphenyl]-4-ol5

1H NMR (400 MHz, CDCl3): δ 7.74 (t, J = 8.0 Hz, 4H, Ar-H), 7.22 (d, J = 8.0 Hz, 2H, Ar-H), 6.89 (d, J = 8.8 Hz, 2H, Ar-H), 4.82 (s, 1H, OH), 2.38 (s, 3H, CH3), ppm.

4'-methyl-[1,1'-biphenyl]-4-carboxylic acid6

1H NMR (400 MHz, DMSO-d6): δ 12.90 (br, 1H, COOH), 8.01 (d, J = 8.0 Hz, 2H, Ar-H), 7.78 (d, J = 8.4 Hz, 2H, Ar-H), 7.64 (d, J = 8.0 Hz, 2H, Ar-H), 7.31 (d, J = 8.0 Hz, 2H, Ar-H), 2.36 (s, 3H, CH3), ppm.

3-phenylpyridine7 1H NMR (400 MHz, CDCl3, TMS): δ 8.85 (d, J = 0.8 Hz, 1H, Py), 8.60 (d, J = 4.8 Hz, 1H, Py), 7.87 (d, J = 8.0 Hz, 1H, Py), 7.58 (d, J = 8.0 Hz, 2H, Ph), 7.48 (t, J = 8.0 Hz, 2H, Ph), 7.40 (t, J = 7.6 Hz, 1H, Py), 7.37-7.34 (m, 1H, Ph), ppm.

2-methoxyl-5-phenylpyridine8

1H NMR (400 MHz, CDCl3, TMS): δ 8.39 (s, 1H, , Py), 7.78 (dd, J = 8.4 Hz, J = 2.4 Hz, 1H), 7.53-7.51 (d, J = 7.6 Hz, 2H, Py), 7.43 (t, J = 7.2 Hz, 2H, Ph), 7.34 (t, J = 7.2 Hz, 1H, Ph), 6.81 (d, J = 8.4 Hz, 1H, Ph), 3.98 (s, 3H, OCH3), ppm.


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Reference

1 C. Deng, S.Guo, Y. Xie and J. Li, Eur. J. Org. Chem., 2007, 1457.

2 D. Saha, K. Chattopadhyay and B. Ranu, Tetrahedron Lett., 2009, 50, 1003.

3 Z. Weng, L. Koh and T. Hor, J. Organomet. Chem., 2004, 689, 18.

4 E. Shirakawa, K.-I. Itoh, T. Higashino, T. Hayashi, J. Am. Chem. Soc., 2010, 132, 15537.

5 S. A. Moteki, J. M. Takacs, Angew. Chem., Int. Ed., 2008, 47, 894.

6 K. Nemoto, H. Yoshida, N. Egusa, N. Morohashi, T. Hattori, J. Org. Chem., 2010, 75, 7855.

7 S. Shi and Y. Zhang, Green Chem., 2008, 10, 868.

8 J. Li, Q. Zhu and Y. Xie, Tetrahedron, 2006, 62, 10888.


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Characterization Data of Imidazolium Salts

MeOPEG550OSO2CH3

Imidazolium salt 1


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Imidazolium salt 2


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Imidazolium salt 3


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1H NMR Spectra for all Cross-Coupling Products


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