did not afford any halide-bridged dimeric complexes; instead
the bis-chelated complexes are formed, e.g. [(Cy2AFA)2Pd] and
[(tBu2AFA)2Pd].
at -78 ◦C. The mixture was stirred for 1.5 h, and then allowed
to warm to -40 ◦C. The colour of the solution turned from
yellow-orange to dark orange. A solution of di-m-chloro-bis(N,N-
dimethylbenzylamine-2-C,N)dipall◦adium (0.227 g, 0.411 mmol)
in THF (15 cm3) was added at -40 C. The colour of the reaction
mixture turned to dark red. The mixture was stirred overnight at
room temperature. The solvent was removed in vacuo and the crude
product was washed with a solvent mixture of toluene–hexane
(2 : 1) and the residue was subsequently dissolved in a CH2Cl2–
hexane mixture (8 : 1) and filtered through celite to remove LiCl.
The solvent was removed in vacuo and the resulting residue washed
with hexane which yielded pure product. Yield: 0.012 g (3%).
Crystals suitable for X-ray analysis were obtained from slow
diffusion of hexane into a concentrated solution of the product
Experimental
All reactions and manipulations of moisture- and air-sensitive
compounds were carried out in an atmosphere of dry nitrogen
using Schlenk techniques or in a conventional nitrogen-filled
glovebox (Saffron Scientific), fitted with oxygen and water scav-
enging columns. All the solvents were freshly distilled over an
appropriate drying agent and further degassed before use where
necessary. Toluene, THF, diethyl ether, and hexane were all dis-
tilled from Na/benzophenone under a nitrogen atmosphere. NMR
solvents were degassed using freeze-thaw cycles and stored over
in CH2Cl2. H NMR (CDCl3, 250 MHz, 25 ◦C): d 2.30 (s, 3H,
1
˚
4 A molecular sieves. All solvents and reagents were purchased
CH3), 2.53 (s, 3H, CH3), 3.72 (d, 1H, J = 13.54 Hz), 3.89 (d,
1H, J = 13.54 Hz), 6.40 (t, 1H, H4, J = 3.63 Hz), 6.58-6.85 &
6.89-7.87 (m, 14H, Ar), 6.86 (dd, 1H, H3, J = 3.63, 1.65 Hz), 6.87
(dd, 1H, H5, J = 3.30, 1.32 Hz), 8.61 (s, 1H, H7), 8.65 (s, 1H,
from Sigma-Aldrich, Fischer or Acros and used as received unless
otherwise stated. NMR spectra were recorded on Bruker AC
250 and 360 MHz spectrometers operating at room temperature.
1H and 13C chemical shifts are reported in ppm relative to
SiMe4 (d = 0) and were referenced internally with respect to
the protio solvent impurity and the 13C resonances respectively.
Multiplicities and peak types are abbreviated: singlet, s; doublet,
d; triplet, t; multiplet, m; broad, br; aromatic, ar. Mass spectra
were recorded on a Kratos MS50TC spectrometer (FAB-MS).
Elemental analyses were performed using a Perkin Elmer 2400
CHN Elemental Analyser.
H1); 13C{ H} NMR (CDCl3, 90.6 MHz, 25 ◦C): d 158.83 (C1),
1
158.40 (C7), 149.82, 148.54, 146.88, 146.55, 134.67, 132.47, 131.96,
129.30, 128.79, 124.79, 124.72, 124.60, 123.99, 123.72, 121.55,
121.51, 121.06, 119.37, 119.06 (C4), 73.66 (C, CH2), 52.13 (C,
NCH3), 51.42 (C, NCH3); MS (EI, m/z): 511(M+). Anal. Calcd
for C28H27PdN3: C, 65.69; H, 5.32; N, 8.21 Found: C, 65.29; H,
5.41; N, 8.31.
Synthesis of [(Cy2AFA)2Pd] (3)
Synthesis of [(Ph2AFA)Pd(CH3)(DMAP)] (1)
To a red solution of Cy2AFAH (0.311 g, 1.097 mmol) in toluene
(25 cm3), 0.822 cm3 (1.316 mmol) of CH3Li (1.6 M in diethyl ether)
were added and the mixture was stirred at RT for 1 h. A pale
red solution of (PhCN)2PdCl2 (0.421 g, 1.097 mmol) in toluene
To a solution of Ph2AFAH (0.538 g, 1.98 mmol) in toluene
(40 cm3), 1.24 cm3 (1.98 mmol) of nBuLi (1.6 M in hexane)
were added and the mixture was stirred for 1 h. To a solution
of [(COD)Pd(CH3)(Cl)] (0.524 g, 1.98 mmol) in toluene (20 cm3),
DMAP (0.241 g, 1.98 mmol) was added and the resulting brown
suspension was transferred into the solution of the deprotonated
ligand. The colour of the reaction mixture immediately became
dark red. The mixture was stirred overnight at room temperature.
After filtration through celite, the volume of the solvent was
reduced to ca. 2/3 under vacuum. Upon storage at -10 ◦C, the
red product precipitated. Suitable crystals for X-ray analysis were
obtained by slow diffusion of hexane into a dichloromethane
◦
(50 cm3) was stirred at 50 C for 1 h and then transferred to the
deprotonated ligand. The dark red reaction mixture was stirred
at room temperature over night. After filtration through celite,
the volume of the solvent was reduced to ca. 2/3 under vacuum
and then acetonitrile was added to precipitate the product from
the unreacted ligand. The solution was decanted and the solid
orange product was dried under vacuum. Crystals suitable for
X-ray analysis were obtained by slow evaporation of a solution
in a mixture of toluene and acetonitrile solvents under nitrogen.
Yield: 0.07 g (10%). 1H NMR (CDCl3, 250 MHz, 25 ◦C): d 7.71 (s,
2H, H1/H7), 6.54 (d, 2H, H3/H5, J = 3.30 Hz), 6.3 (t, 1H, H4, J =
1
solution of the product. Yield: 0.30 g (44%). H NMR (CDCl3,
◦
250 MHz, 25 C): d 8.37 (s, 1H, H1), 8.29 (s, 1H, H7), 7.81 (d,
2H, DMAP, J = 7 Hz), 7.66-6.89 (m, 10H, C6H5), 6.83 (dd, 1H,
H5, J = 5.28, 2.31 Hz), 6.80 (dd, 1H, H3, J = 5.6, 2.31 Hz), 6.35
(t, 1H, H4, J = 3.63 Hz), 6.12 (d, 2H, DMAP, J = 7.26 Hz), 2.92
1
3.30 Hz), 3.11 (2H, ipso-CyH), 0.96-1.81(m, 20H, CyH);13C{ H}
NMR (CDCl3, 90.6 MHz, 25 ◦C): d 160.97 (C1/C7), 127.27
(C3/C5), 116.89 (C4), 115.54 (C2/C6), 65.31 (ipso-C, Cy), 37.02
(C, Cy), 32.79 (C, Cy), 26.24 (C, Cy); MS (EI, m/z): 672.4 (M+).
Anal. Calcd for C38H54N4Pd: C, 67.79; H, 8.08; N, 8.32. Found: C,
67.09; H, 7.98; N, 8.11.
1
(s, 6H, DMAP), -0.1 (s, 3H, CH3–Pd);13C{ H} NMR (CDCl3,
90.6 MHz, 25 ◦C): d 163.74 (C1), 160.34 (C7), 154.06, 153.92,
152.87, 150.95 (C, DMAP), 133.02, 132.62, 128.79, 128.68, 124.78,
124.15, 123.94, 122.55, 117.98, 117.81, 117.54, 107.21 (C, DMAP),
39.40 (N-CH3), 1.37 (Pd-CH3); MS (FAB, m/z): 515 (M+). Anal.
Calcd for C27H28N4Pd: C, 62.97; H, 5.48; N, 10.88. Found: C,
63.54; H, 5.56; N, 10.52.
Synthesis of N,N¢-bis(2,6-diisopropylphenyl)-6-aminofulvene-2-
aldimine (4)
A
solution of 6-dimethylaminofulvene-2-N,N¢-dimethyl-
Synthesis of [(Ph2AFA)(N,N-dimethylbenzylamine-2-C,N)-Pd(II)]
(2)
aldimmonium chloride (2.01 g, 9.45 mmol) in dry ethanol
(35 cm3) was refluxed with 2,6-diisopropylaniline (3.54 cm3,
18.80 mmol) for 12 h. The solvent and volatiles were removed in
vacuo. The resulting solid was then refluxed in hexane (150 cm3)
To a solution of Ph2AFAH (0.224 g, 0.822 mmol) in THF
(15 cm3) was added nBuLi (0.56 cm3, 1.6M in hexane, 0.91 mmol)
This journal is
The Royal Society of Chemistry 2010
Dalton Trans., 2010, 39, 1591–1597 | 1595
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