Recoverable Homogeneous Palladium(0) Catalyst for Cross-Coupling Reactions
FULL PAPER
+
4
1
2
8
1
-Nitrobiphenyl (8c): Pale yellow solid. Yield: 0.048 g (69%). M.p.
H) ppm. GC–MS: m/z (%) = 134 (100) [M] , 119 (89), 91 (96), 65
(63).
[
8f]
1
11–112 °C (ref. 107.5–108.0 °C). H NMR (200 MHz, CDCl
3
,
5 °C): δ = 7.38–7.56 (m, 3 H), 7.56–7.66 (m, 2 H), 7.71 (d, J =
.8 Hz, 2 H), 8.27 (d, J = 8.8 Hz, 2 H) ppm. GC–MS: m/z (%) =
4-Methylstyrene (12f): Colourless oil. Yield: 0.029 g (36%). 1
NMR (200 MHz, CDCl , 25 °C): δ = 2.34 (s, 3 H), 5.17 (d, J =
H
+
99 (99) [M] , 169 (51), 152 (100).
3
1
1
0.8 Hz, 1 H), 5.69 (d, J = 17.6 Hz, 1 H), 6.69 (dd, J = 17.6 and
4
-Fluorobiphenyl (8d): Colourless solid. Yield: 0.021 g (35%). M.p.
0.8 Hz, 1 H), 7.12 (d, J = 8.0 Hz, 2 H), 7.30 (d, J = 8.0 Hz, 2
[
19]
1
72–73 °C (ref.
3
74.5 °C). H NMR (200 MHz, CDCl , 25 °C): δ
+
H) ppm. GC–MS: m/z (%) = 118 (100) [M] , 91 (58).
=
7.13 (t, J = 8.8 Hz, 2 H), 7.30–7.65 (m, 7 H) ppm. GC–MS: m/z
+
(%) = 172 (100) [M] , 85 (51).
ESI-MS: All experiments were performed with a commercially
4
-tert-Butylbiphenyl (8e): Colourless solid. Yield: 0.031 g (43%).
available quadrupole mass spectrometer fitted with an electrospray
1
3
M.p. 44–46 °C. H NMR (200 MHz, CDCl , 25 °C): δ = 1.36 (s, 9 ion source. The mixtures specified in Table 3 were dissolved in 1,4-
H), 7.22–7.62 (m, 9 H) ppm. GC–MS: m/z (%) = 210 (77) [M] ,
1
+
dioxane and the solution was directly introduced into the mass
spectrometer ion source by use of a Rheodyne injector with a 20 µL
sample loop. The mobile phase flow (acetonitrile/water, 70:30 v/v,
95 (100), 167 (78), 152 (52), 83 (51).
4
4
7
-Methylbiphenyl (8f): Colourless solid. Yield: 0.023 g (39%). M.p.
–
1
1
00 µLmin ) was delivered to the vaporization nozzle of the elec-
1
3–44 °C. H NMR (200 MHz, CDCl
3
, 25 °C): δ = 2.38 (s, 3 H),
trospray ion source with the aid of a P2000 HPLC pump and nitro-
gen was employed as both a drying and a nebulizing gas. The in-
strument was operated in the positive ion mode (ESI+). The typical
ESI conditions used were: probe tip voltage of 3 kV, capillary tem-
+
.20–7.60 (m, 9 H) ppm. GC–MS: m/z (%) = 168 (100) [M] , 152
(80), 82 (44).
3
-Methylbiphenyl (8g): Colourless oil. Yield: 0.017 g (30%). 1
H
3
NMR (200 MHz, CDCl , 25 °C): δ = 2.44 (s, 3 H), 7.12–7.22 (m, perature of 160 °C and skimmer cone voltage of 30 eV. Typically
1
H), 7.30–7.49 (m, 6 H), 7.53–7.65 (m, 2 H) ppm. GC–MS: m/z 10–20 spectra scans were performed. Theoretical isotope patterns
+
(%) = 168 (100) [M] , 152 (65), 83 (31).
were calculated by use of the Isoform programme. All the mass
acquisitions shown in Table 3 were repeated with the skimmer cone
voltage set at 10 eV and 80 eV, but the best spectra were obtained
at 30 eV.
-Methylbiphenyl (8h): Colourless oil. Yield: 0.013 g (23%). 1
2
H
3
NMR (200 MHz, CDCl , 25 °C): δ = 2.27 (s, 3 H), 7.20–7.46 (m,
9
+
H) ppm. GC–MS: m/z (%) = 168 (100) [M] , 152 (82), 83 (41).
4
(
-Methoxy-4Ј-methylbiphenyl (9f): Colourless solid. Yield: 0.027 g
40%). M.p. 106–108 °C (ref.[8f] 107–108 °C). H NMR (200 MHz,
1
Acknowledgments
CDCl
3
, 25 °C): δ = 2.37 (s, 3 H), 3.83 (s, 3 H), 6.95 (d, J = 8.8 Hz,
2
H), 7.21 (d, J = 8.0 Hz, 2 H), 7.44 (d, J = 8.0 Hz, 2 H), 7.50 (d,
+
Financial support from the Spanish Ministry of Education and Sci-
ence (Project CTQ-2005–04968 and predoctoral grant to J. M.), the
J = 8.8 Hz, 2 H) ppm. GC–MS: m/z (%) = 198 (100) [M] , 183
86), 155 (53).
(
“Generalitat de Catalunya” (Project 2005SGR00305), and the Uni-
4-Fluoro-4Ј-methoxybiphenyl (10b): Colourless solid. Yield: 0.029 g
versity of Girona (predoctoral grant to I. G.) is gratefully acknowl-
edged.
1
3
(42%). M.p. 84–86 °C. H NMR (200 MHz, CDCl , 25 °C): δ =
3.83 (s, 3 H), 6.96 (d, J = 8.8 Hz, 2 H), 7.08 (t, J = 8.8 Hz, 2 H),
+
7
.36–7.55 (m, 4 H) ppm. GC–MS: m/z (%) = 202 (99) [M] , 187
(
97), 159 (100), 133 (89).
[
1] a) A. de Meijere, F. Diederich (Eds.), Metal-Catalyzed Cross-
Coupling Reactions, 2nd ed., Wiley-VCH, Weinheim, 2004, vol.
3
-Phenylthiophene (11a): Colourless solid. Yield: 0.013 g (24%).
1
, p. 41; b) N. Miyaura, A. Suzuki, Chem. Rev. 1995, 95, 2457–
483; c) A. Suzuki, J. Organomet. Chem. 1999, 576, 147–168;
1
M.p. 76–78 °C. H NMR (200 MHz, CDCl
(
3
, 25 °C): δ = 7.25–7.46
2
m, 6 H), 7.53–7.64 (m, 2 H) ppm. GC–MS: m/z (%) = 160 (100)
d) S. Kotha, K. Lahiri, D. Kashinath, Tetrahedron 2002, 58,
633–9695; e) N. Miyaura, Top. Curr. Chem. 2002, 219, 11–59.
+
[M] , 115 (68).
9
[
2] a) M. Moreno-Mañas, R. Pleixats, R. M. Sebastián, A. Vallrib-
era, A. Roglans, J. Organomet. Chem. 2004, 689, 3669–3684; b)
M. Moreno-Mañas, R. Pleixats, A. Roglans, R. M. Sebastián,
A. Vallribera, Arkivoc 2004, iv, 109–129; c) For a complete
structural analysis of 1 see: A. Pla-Quintana, A. Roglans, J. V.
de Julián-Ortiz, M. Moreno-Mañas, T. Parella, J. Benet-Buch-
holz, X. Solans, Chem. Eur. J. 2005, 11, 2689–2697.
4
-(3-Thienyl)anisole (11b): Colourless solid. Yield: 0.016 g (24%).
1
M.p. 127–129 °C. H NMR (200 MHz, CDCl
3
, 25 °C): δ = 3.83 (s,
3
8
1
H), 6.93 (d, J = 8.8 Hz, 2 H), 7.34 (br. abs, 3 H), 7.52 (d, J =
.8 Hz, 2 H) ppm. GC–MS: m/z (%) = 190 (100) [M] , 175 (99),
47 (73).
+
4
-Nitrostyrene (12c): Pale yellow oil. Yield: 0.030 g (60%). 1
, 25 °C): δ = 5.50 (d, J = 10.8 Hz, 1 H),
H
[
3] a) A. Llobet, E. Masllorens, M. Moreno-Mañas, A. Pla-Quin-
tana, M. Rodríguez, A. Roglans, Tetrahedron Lett. 2002, 43,
NMR (200 MHz, CDCl
5
7
3
.93 (d, J = 17.4 Hz, 1 H), 6.78 (dd, J = 17.4 and 10.8 Hz, 1 H),
1425–1428; b) J. Masllorens, M. Moreno-Mañas, A. Pla-Quin-
.53 (d, J = 8.0 Hz, 2 H), 8.18 (d, J = 8.0 Hz, 2 H) ppm. GC–MS:
tana, A. Roglans, Org. Lett. 2003, 5, 1559–1561; c) J. Masllor-
ens, S. Bouquillon, A. Roglans, F. Hénin, J. Muzart, J. Or-
ganomet. Chem. 2005, 690, 3822–3826; d) A. Pla-Quintana, A.
Roglans, Arkivoc 2005, ix, 51–62.
+
m/z (%) = 149 (100) [M] , 119 (88), 103 (80), 91 (91), 77 (95).
1
4
-tert-Butylstyrene (12e): Colourless oil. Yield: 0.032 g (43%). H
3
NMR (200 MHz, CDCl , 25 °C): δ = 1.32 (s, 9 H), 5.19 (d, J =
1
1
[
4] a) S. Darses, T. Jeffery, J. P. Genêt, J. L. Brayer, J. P. Demoute,
Tetrahedron Lett. 1996, 37, 3857–3860; b) S. Darses, T. Jeffery,
J. L. Brayer, J. P. Demoute, J. P. Genêt, Bull. Soc. Chim. Fr.
1996, 133, 1095–1102; c) S. Sengupta, S. Bhattacharyya, J. Org.
Chem. 1997, 62, 3405–3406; d) S. Darses, J. P. Genêt, J. L.
Brayer, J. P. Demoute, Tetrahedron Lett. 1997, 38, 4393–4396;
e) S. Sengupta, S. K. Sadhukhan, S. Bhattacharyya, J. Guha,
J. Chem. Soc., Perkin Trans. 1 1998, 407–410; f) S. Sengupta,
S. K. Sadhukhan, Tetrahedron Lett. 1998, 39, 715–718; g) S.
0.8 Hz, 1 H), 5.70 (d, J = 17.6 Hz, 1 H), 6.70 (dd, J = 17.6 and
0.8 Hz, 1 H), 7.35 (s, 4 H) ppm. GC–MS: m/z (%) = 160 (72)
+
[
M] , 145 (98), 117 (100), 105 (69), 91 (61), 77 (53).
-Methoxystyrene (12b): Colourless oil. Yield: 0.019 g (41%). 1
NMR (200 MHz, CDCl , 25 °C): δ = 3.81 (s, 3 H), 5.12 (d, J =
4
H
3
1
1
0.8 Hz, 1 H), 5.60 (d, J = 17.6 Hz, 1 H), 6.66 (dd, J = 17.6 and
0.8 Hz, 1 H), 6.86 (d, J = 8.6 Hz, 2 H), 7.34 (d, J = 8.6 Hz, 2
Eur. J. Org. Chem. 2007, 158–166
© 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
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