1
d 64.8 (s). 13C{ H} NMR (125 MHz, CDCl3, 298 K, relative to
alumina using dichloromethane as the eluent. Slow evaporation of
the solvent yielded dbcpe as a white solid. Yield: 0.42 g, 18%. 1H
NMR (500 MHz, CDCl3, 298 K, relative to Me4Si): d 1.96–1.97 (t,
4H, J = 3.8 Hz, –CH2CH2–), 3.74–3.75 (m, 32H, –OCH2–), 3.85–
3.91 (m, 16H, –OCH2–), 4.00–4.03 (m, 8H, –OCH2–) 4.12–4.13
Me4Si): d 152.28, 149.04, 126.48, 120.33, 119.48, 112.92, 71.09,
+
70.67, 69.12, 68.68, 28.72. Positive FAB-MS: m/z 1426 {M} ,
+
1346 {M − Br} . Elemental analyses, Found (%): C 47.91, H 5.60;
1
2
Calcd for C58H80Br2O20P2Pd· CH2Cl2 (%): C 47.87, H 5.56.
1
(m, 8H, –OCH2–), 6.78–6.99 (m, 12H, –C6H3–). 31P{ H} NMR
(202 MHz, CDCl3, 298 K, relative to 85% H3PO4): d −11.51 (s).
[Pd(dbcpe)I2], 3
1
13C{ H} NMR (125 MHz, CDCl3, 298 K, relative to Me4Si):
A suspension of PdI2 (15.5 mg, 0.043 mmol) in benzonitrile (1 ml)
was heated to 100 ◦C. After 20 min, most of the PdI2 dissolved to
give a black solution. To this was added a benzene solution (30 ml)
of dbcpe (50 mg, 0.043 mmol) and the mixture was heated to reflux
for 1 h. The mixture was then allowed to cool to room temperature.
The solvent was removed under reduced pressure, and the crude
product was recrystallised by vapour diffusion of diethyl ether into
a concentrated dichloromethane solution to yield yellow crystals.
d 149.20, 126.26, 124.58, 117.79, 115.62, 113.59, 71.10, 70.43,
+
69.43, 69.36, 68.75. Positive FAB-MS: m/z 1158 {M} . Elemental
analyses, Found (%): C 60.22, H 6.90; Calcd for C58H80O20P2 (%):
C 60.10, H 6.96.
1,2-Bis[bis(3,4-dimethoxyphenyl)phosphino]ethane, ddmppe
The procedure was similar to that described for the preparation
of dbcpe except 4-bromoveratrole was used in place of 4ꢀ-
bromobenzo-15-crown-5. Yield: 0.33 g, 26%. 1H NMR (500 MHz,
CDCl3, 298 K, relative to Me4Si): d 1.92 (t, 4H, J = 4.2 Hz,
–CH2CH2–), 3.63 (s, 12H, –OCH3), 3.73 (s, 12H, –OCH3), 6.72–
1
Yield: 48 mg, 73%. H NMR (500 MHz, CDCl3, 298 K, relative
to Me4Si): d 2.17–2.23 (t, 4H, J = 6.4 Hz, –CH2CH2–), 3.72–3.79
(m, 32H, –OCH2–), 3.85–3.88 (m, 8H, –OCH2–), 3.91–3.93 (m,
8H, –OCH2–), 4.08–4.10 (m, 8H, –OCH2–), 4.16–4.17 (m, 8H,
–OCH2–), 6.88–6.89 (m, 4H, –C6H3–), 7.21–7.23 (m, 4H, –
1
6.85 (m, 12H, –C6H3–). 31P{ H} NMR (202 MHz, CDCl3, 298 K,
1
relative to 85% H3PO4): d −12.33 (s). 13C{ H} NMR (125 MHz,
C6H3–), 7.38–7.40 (m, 4H, –C6H3–). 31P{ H} NMR (202 MHz,
1
CDCl3, 298 K, relative to 85% H3PO4): d 63.0 (s). 13C{ H}
1
CDCl3, 298 K, relative to Me4Si): d 149.87, 149.06, 129.77, 125.44,
115.55, 111.36, 55.72, 55.65, 24.63. Positive FAB-MS: m/z 637
NMR (125 MHz, CDCl3, 298 K, relative to Me4Si): d 151.90,
+
{M} . Elemental analyses, Found (%): C 63.83, H 6.33; Calcd for
148.54, 126.62, 121.22, 119.59, 112.77, 71.00, 70.22, 69.11, 68.58,
+
+
C34H40O8P2 (%): C 63.94, H 6.31.
28.93. Positive FAB-MS: m/z 1520 {M} , 1393{M − I} .
Elemental analyses, Found (%): C 44.94, H 5.26; Calcd for
1
2
C58H80I2O20P2Pd· CH2Cl2 (%): C 44.98, H 5.23.
[Pd(dbcpe)Cl2], 1
To a hot benzene solution (5 ml) of bis(benzonitrile)palladium(II)
chloride (33 mg, 0.086 mmol) was added dbcpe (100 mg,
0.086 mmol) at room temperature and the resulting solution was
heated to reflux for 1 h. The reaction mixture was allowed to
cool to room temperature and filtration gave the crude product.
Recrystallisation was accomplished by vapour diffusion of diethyl
ether into a concentrated dichloromethane solution of the product
to give pale yellow crystals. Yield: 87 mg, 76%. 1H NMR
(500 MHz, CDCl3, 298 K, relative to Me4Si): d 2.31–2.39 (t, 4H,
J = 5.8 Hz, –CH2CH2–), 3.73–3.75 (m, 32H, –OCH2–), 3.82–3.85
(m, 8H, –OCH2–), 3.92–3.93 (m, 8H, –OCH2–), 4.10–4.11 (m,
8H, –OCH2–), 4.12–4.14 (m, 8H, –OCH2–), 6.87–6.89 (m, 4H,
–C6H3–), 7.21–7.25 (m, 4H, –C6H3–), 7.54–7.58 (m, 4H, –C6H3–).
[Pd(ddmppe)Cl2], 4
The procedure was similar to that described for the preparation of
1 except ddmppe was used in place of dbcpe. Yield: 54 mg, 77%.
1H NMR (500 MHz, CDCl3, 298 K, relative to Me4Si): d 2.37–
2.48 (t, 4H, J = 6.6 Hz, –CH2CH2–), 3.84 (s, 12H, –OCH3), 3.91
(s, 12H, –OCH3), 6.91–6.93 (m, 4H, –C6H3–), 7.28–7.34 (m, 4H,
–C6H3–), 7.61–7.65 (m, 4H, –C6H3–). 31P{ H} NMR (202 MHz,
1
CDCl3, 298 K, relative to 85% H3PO4): d 62.6 (s). 13C{ H} NMR
1
(125 MHz, CDCl3, 298 K, relative to Me4Si): d 152.27, 149.50,
125.76, 119.74, 116.96, 111.11, 56.44, 56.03, 28.16. Positive FAB-
+
+
MS: m/z 816 {M} , 780 {M–Cl} . Elemental analyses, Found
1
2
(%): C 48.21, H 4.89; Calcd for C34H40Cl2O8P2Pd· CH2Cl2 (%): C
1
31P{ H} NMR (202 MHz, CDCl3, 298 K, relative to 85% H3PO4):
48.27, H 4.81.
1
d 63.7 (s). 13C{ H} NMR (125 MHz, CDCl3, 298 K, relative to
Me4Si): d 152.33, 149.29, 126.08, 119.85, 119.37, 113.03, 71.10,
Physical measurements and instrumentation
+
70.41, 69.20, 68.72, 28.29. Positive FAB-MS: m/z 1336 {M} ,
UV/Vis spectra were obtained on a Hewlett-Packard 8452A
diode array spectrophotometer, and steady-state excitation and
emission spectra on a Spex Fluorolog 111 spectrofluorometer
equipped with a Hamamatsu R-928 photomultiplier tube. Low-
temperature (77 K) spectra were recorded by using an optical
+
1300 {M − Cl} . Elemental analyses, Found (%): C 51.19, H 5.96;
1
2
Calcd for C58H80Cl2O20P2Pd· CH2Cl2 (%): C 50.95, H 5.92.
[Pd(dbcpe)Br2], 2
1
1
1
The procedure was similar to that described for the preparation of
Dewar sample holder. H, 31P{ H} and 13C{ H} NMR spectra
1 except bis(benzonitrile)palladium(II) bromide was used in place
were recorded on a Bruker DRX-500 FT-NMR spectrometer
1
1
of bis(benzonitrile)palladium(II) chloride. Yield: 96 mg, 78%. H
(500 MHz for H, 202 MHz for 31P and 125 MHz for 13C) in
1
1
NMR (500 MHz, CDCl3, 298 K, relative to Me4Si): d 2.27–2.32 (t,
4H, J = 6.6 Hz, –CH2CH2–), 3.72–3.77 (m, 32H, –OCH2–), 3.84–
3.87 (m, 8H, –OCH2–), 3.91–3.94 (m, 8H, –OCH2–), 4.08–4.12
(m, 8H, –OCH2–), 4.13–4.16 (m, 8H, –OCH2–), 6.87–6.89 (m, 4H,
–C6H3–), 7.23–7.25 (m, 4H, –C6H3–), 7.48–7.50 (m, 4H, –C6H3–).
CDCl3 at 298 K. Chemical shifts (in ppm) of H and 13C{ H}
NMR spectra were recorded relative to tetramethylsilane (Me4Si),
while that of 31P{ H} spectra were recorded relative to 85%
1
H3PO4 (external). Positive-ion FAB mass spectra were recorded
on a Finnigan MAT95 mass spectrometer. Elemental analyses
of the new complexes were performed on a Carlo Erba 1106
1
31P{ H} NMR (202 MHz, CDCl3, 298 K, relative to 85% H3PO4):
1806 | Dalton Trans., 2006, 1803–1808
This journal is
The Royal Society of Chemistry 2006
©