8 V. Friebolin, S. Marten and K. Albert, Magn. Reson. Chem., 2010,
48, 111.
9 (a) T. Posset, F. Rominger and J. Blumel, Chem. Mater., 2005, 17,
¨
2005, 690, 3383; (c) R. Fetouaki, A. Seifert, M. Bogza, T. Oeser
¨
586; (b) M. Bogza, T. Oeser and J. Blumel, J. Organomet. Chem.,
and J. Blumel, Inorg. Chim. Acta, 2006, 359, 4865; (d) S. Brenna,
¨
T. Posset, J. Furrer and J. Blumel, Chem.–Eur. J., 2006, 12,
¨
2880.
10 Synthesis of the chelate phosphine ligand 1: (EtO)3Si(CH2)3NH2
(0.58 g, 2.63 mmol) is dissolved in 20 ml of toluene and (CH2O)x
(0.19 g, 5.26 mmol) and Ph2PH (0.98 g, 5.26 mmol) are added. The
suspension turns into a clear solution within 2 h after heating to
60 1C, and is stirred overnight at this temperature. The solvent is
removed in vacuo, and 1.40 g (2.27 mmol, yield 85%) of 1 results as
a clear, viscous liquid. d(1H) (500.1 MHz, C6D6) 7.53–7.04
3
3
(m, Haryl), 3.76 (q, JHH 7.0 Hz, OCH2), 3.63 (d, JPH 3.4 Hz,
PCH2), 3.00 (t, 3JHH 7.1 Hz, CH2CH2N), 1.75 (quint., 3JHH 7.6 Hz,
CH2CH2CH2), 1.57 (t, JHH 7.0 Hz, CH3), 0.65 (t, JHH 8.1 Hz,
3
3
1
SiCH2); d(13C) (125.8 MHz, C6D6) 139.14 (d, JPC 13.7 Hz, Ci),
2
3
133.54 (d, JPC 18.5 Hz, Co), 128.63 (d, JPC 6.6 Hz, Cm), 128.55
3
1
(s, Cp), 59.64 (t, JPC 9.0 Hz, CH2CH2N), 59.23 (dd, JPC 9.3 Hz,
3JPC 5.6 Hz, CH2P), 58.43 (s, OCH2), 20.31 (s, CH2CH2CH2),
18.62 (s, CH3), 8.33 (s, SiCH2); d(31P) (121.5 MHz, C6D6) ꢀ28.2;
MS (EI, 70 eV) m/z 432.1 [M+–PPh2], 199.1 [PPh2+]; MS (HR-EI)
m/z (%, calc.) 432.2098 (100.00, 432.2124) [M+–PPh2].
11 Synthesis of Pd complex 2: (C6H5CN)2PdCl2 (0.074 g, 0.19 mmol)
is dissolved in 10 ml of toluene. Ligand 1 (0.119 g, 0.19 mmol), in
5 ml of toluene, is added dropwise at ambient temperature, and the
orange mixture is stirred for 2 h. Then the solution is concentrated
to about 5 ml and 10 ml of pentane is added. Hereby, a yellow
precipitate forms that is washed two times with 5 ml of pentane and
dried in vacuo. Complex 2 is obtained in quantitative yield (0.148 g,
0.19 mmol). d(1H) (500.1 MHz, CDCl3) 8.87–7.35 (m, Haryl),
Fig. 4 31P HRMAS spectra. Top: batches of 2i and 5i after being
stirred together in acetone overnight. Bottom: batches of 6i and 1i,
stirred for several minutes. Middle section: spectra recorded at the
given time intervals after mixing batches of 1i and 6i in acetone.
3
2
4
3.74 (q, JHH 7.0 Hz, OCH2), 3.32 (dd, JPH 4.1 Hz, JPH 2.5 Hz,
PCH2), 2.63 (t, 3JHH 7.2 Hz, CH2CH2N), 1.46 (quint., 3JHH 7.0 Hz,
CH2CH2CH2), 1.15 (t, JHH 7.0 Hz, CH3), 0.38 (t, JHH 7.9 Hz,
3
3
3
SiCH2); d(13C) (125.8 MHz, CDCl3) 133.85 (virt. t, JPC 5.0 Hz,
Cm), 131.43 (s, Cp), 128.92(t, 1JPC 57.3 Hz, 3JPC 7.0 Hz, Ci), 128.58
2/4
(virt. t,
J
5.9 Hz, Co), 65.08 (t, 3JPC 10.0 Hz, CH2CH2N), 58.45
PC
1 3
(s, OCH2), 56.58 (dd, JPC 46.4 Hz, JPC 1.7 Hz, PCH2), 18.56
(s, CH2CH2CH2), 18.29 (s, CH3), 7.66 (s, SiCH2); d(31P)
(121.5 MHz) 7.59 (C6D6), 7.79 (CDCl3); MS (FAB) m/z 795.1
[M+], 760.1 [M+–Cl], 723.2 [M+–2Cl], 538.1 [M+–2Cl–PPh3],
305.0 [PdPPh2+]; HRMS (FAB) m/z (%, calc.) 793.1024 (18.3%,
793.1056) [M+], 758.1420 (99.8%, 758.1367) [M+–Cl], 723.1647
(23.5%, 723.1679) [M+–2Cl]; UV/VIS l (e) 260 nm (17645),
324 nm (5235).
Fig. 5 Recycling characteristics of 2i in the indicated solvents. CuI
and the substrates PhI and PhCCH are added for each cycle.18
This material is based upon work supported by The Welch
Foundation (A-1706), the National Science Foundation
(CHE-0911207), INSTRACTION, and DFG (SFB 623).
12 CCDC 795029. Crystal data of 2: orthorhombic, space group
P212121,
C37H49Cl6N1O3P2Pd1Si1 (964.90),
13.4269(8), c = 28.789(2) A, V = 4367.9(5) A3, Dc = 1.467 g cmꢀ3
Z
=
4, 489 parameters,
T
=
100(2) K,
a
=
11.2996(7), =
b
,
F000 = 1976, m = 0.928 mmꢀ1, 46 007 refl. measd, 10 832 unique
(Rint 0.034), final R1 = 0.034, wR2 = 0.078, absolute structure
parameter (Flack value) ꢀ0.011(18). We found two molecules of
dichloromethane (DCM) as crystal inclusion. Disorder effects were
refined at one ethyl group (85 : 15% multiplicity) and at one DCM
molecule (50 : 50% multiplicity)w.
Notes and references
1 Metal-Catalyzed Cross-Coupling Reactions, ed. F. Diederich and
A. De Meijere, Wiley-VCH, Weinheim, 2004.
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and G. Rothenberg, Chem.–Eur. J., 2007, 13, 6908.
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(b) J. Dupont and J. D. Scholten, Chem. Soc. Rev., 2010, 39, 1780;
13 Merck silica (average pore diameter 40 A, particle size
0.063–0.2 mm, specific surface area 750 m2 gꢀ1), dried 4 d in vacuo
at 400 1C.
14 C. Merckle and J. Blumel, Chem. Mater., 2001, 13, 3617.
¨
15 J. R. Black, W. Levason, M. D. Spicer and M. Webster, J. Chem.
Soc., Dalton Trans., 1993, 3129.
(c) K. Kohler, R. G. Heidenreich, S. S. Soomro and S. S. Prockl,
¨
Adv. Synth. Catal., 2008, 350, 2930.
¨
16 Y. Yang, B. Beele and J. Blumel, J. Am. Chem. Soc., 2008, 130,
3771.
¨
6 T. Posset and J. Blumel, J. Am. Chem. Soc., 2006, 128, 8394.
¨
and J. Blumel, Top. Catal., 2005, 34, 5; (c) S. Reinhard, P. Soba,
¨
7 (a) J. Blumel, Coord. Chem. Rev., 2008, 252, 2410; (b) C. Merckle
17 J. Blumel, J. Am. Chem. Soc., 1995, 117, 2112.
¨
18 Reaction temperature 25 1C; surface coverage of 2i: 10.6 molecules
per 100 nm2; ratio solvent:piperidine 2 : 1; 2i : 1i 1 : 1; ratio Pd :
Cu : PhI : PhCCH 0.04 : 0.05 : 1.00 : 1.50; PhI concentration
1.6 mmol lꢀ1; maximal reaction time per cycle 6 h.
¨
F. Rominger and J. Blumel, Adv. Synth. Catal., 2003, 345, 589;
¨
(d) B. Beele, J. Guenther, M. Perera and M. Stach, New J. Chem.,
2010, 34, 2729.
c
This journal is The Royal Society of Chemistry 2011
Chem. Commun., 2011, 47, 2059–2061 2061