2340
M. Janka et al. / Inorganica Chimica Acta 357 (2004) 2339–2344
tris(pyridyl)benzene ligand with [Pd(OTf)2(dppp)] is
described also.
trimethylstannylpyridine (2.4 g, 9.9 mmol) and 1,3-dib-
romobenzene (0.78 g, 3.3 mmol), and the mixture was
stirred for three days under reflux. The solvent was re-
moved and the solid was dissolved in CH2Cl2 and wa-
shed several times with water. The organic phase was
2
. Experimental
dried over anhydrous MgSO . After removal of the
4
All reactions were carried out under an atmosphere
of argon. All the solvents were distilled prior to use.
solvent, the solid was chromatographed on silica gel
using ethyl acetate/hexane (6:4). The resulting material
was dissolved in CH2Cl2 (30 ml), and 2 N HCl (40 ml)
was added, and the heterogeneous mixture was stirred
for 1 h. The aqueous phase was treated with 2 N NaOH
until it was basic to phenolphthalein indicator, then it
was extracted three times with CH2Cl2. The combined
CH Cl solutions were dried over anhydrous MgSO .
[
M(OTf)2(dppp)] (M ¼ Pd, Pt) were prepared as re-
1 31 1
ported previously. H and P{ H} NMR spectra were
recorded on a Bruker ARX-500 or Avance 300, or a
Varian Unity plus 300 spectrometer. Mass spectra were
obtained on a JEOL M Station-JMS700 instrument.
Microanalyses were performed by Atlantic Microlab,
Inc., Norcross, GA.
2
2
4
Removal of the solvent afforded the desired product
þ
(
0.56 g, 73%, R ¼ 0:2). HRMS (NBA) in ESI mode:
f
1
2
14
þ
Calc. for C16H12 N : 232.1000. Found: 232.1001. H
2
1
2
.1. Preparation of 3-trimethylstannylpyridine
NMR (CDCl3): H 7.42–7.96 (m), 8.65 (d, JHH ¼ 4:3
1
3
1
To an ether solution (70 ml) of 3-bromopyridine (1.5
ml, 0.016 mol) at )78 ꢁC was added dropwise a solution
of BuLi in hexane (1.6 M, 11.0 ml, 0.016 mol). After 3
Hz), 8.92 (d, JHH ¼ 4:3 Hz). C{ H} NMR: dC 124.1,
126.5, 127.3, 130.3, 134.9, 136.7, 139.2, 148.8, 149.2.
n
h, Me SnCl (3.8 g, 0.019 mol) in ether (30 ml) was added
3
2.4. Preparation of 1,3-di(4-pyridyl)benzene (2)
over a period of 10 min at )78 ꢁC. The reaction mixture
was stirred for a further 30 min at )78 ꢁC, then slowly
warmed up to room temperature. The solution was
washed several times with water (30 ml) and the organic
phase was dried over MgSO4. The solvent was removed
and the resulting oil was chromatographed on silica gel
This compound was prepared similarly, starting from
4-trimethylstannylpyridine and 1,3-dibromobenzene.
The product was obtained as an off-white solid (0.26 g,
þ
84%). LRMS in ESI mode, m=z (relative intensity
calculated, observed) for C16H12N : 232 (100, 100), 233
þ
2
1
using ethyl acetate/hexane (6:4), and the product was
1
(19, 19). H NMR (CDCl3): dH 7.57–7.80 (m), 8.73 (d,
13
1
obtained as a colorless oil (3.2 g, 83%, R ¼ 0:66). H
JHH ¼ 5:7 Hz), 8.77 (d, J ¼ 5:7 Hz). C{ H} NMR:
HH
f
2
NMR (CDCl ): dH 0.24 (s,
J
119
¼ 56 Hz,
dC 121.9, 125.9, 127.8, 130.1, 139.4, 148.0, 150.6.
2.5. Preparation of 1,3,5-tri(4-pyridyl)benzene (3)
3
SnH
2
J
117SnH
¼ 54 Hz, SnCH ), 6.87 (m), 7.41 (m), 8.18 (m),
3
13 1 1
8
3
.33 (m, C5H4N). C{ H} NMR: dC )9.7 ( J119
¼
SnC
1
59 Hz, J
117SnC
¼ 343 Hz, CH3), 123.6 (JSnC ¼ 32 Hz,
1
1
CH), 136.8 ( J119
¼ 412 Hz, J117
¼ 393 Hz, ipso
This compound was prepared similarly, starting from
4-trimethylstannylpyridine and 1,3,5-tribromobenzene.
The product was obtained as an off white solid (1.13 g,
SnC
SnC
C), 143.1 (JSnC ¼ 28 Hz, CH), 148.9 (CH), 155.1
(
JSnC ¼ 40 Hz, CH).
7
culated, observed) for C H N
3%). LRMS in FAB mode, m=z (relative intensity cal-
þ
þ
(MH ): 310 (100,
2
.2. Preparation of 4-trimethylstannylpyridine
2
1
16
3
1
1
00), 311 (25, 27). H NMR (CDCl ): dH 7.63 (s), 8.46
3
1
3
1
This compound was obtained similarly from free 4-
(d, JHH ¼ 5:5 Hz), 8.75 (d, JHH ¼ 5:5 Hz). C{ H}
NMR: dC 121.6, 127.0, 129.2, 138.2, 150.4.
bromopyridine (obtained by stirring 4-bromopyridine
hydrochloride (2.0 g, 10.3 mmol) and diethylamine (20
ml) overnight in the absence of light in THF (50 ml)).
The product was obtained a colorless an oil (2.6 g, 81%,
2.6. Preparation of [Pd
2
(l-1)
2
(dppp)
2
](OTf)
4
ꢀ 2H
2
O
1
2
R ¼ 0:65). H NMR (CDCl ): dH 0.20 (s, J
119SnH
¼ 56
[Pd(OTf) (dppp)] (0.035 g, 0.043 mmol) and 1 (0.01 g,
2
f
3
2
Hz, J117
¼ 54 Hz, SnCH ), 7.17–7.33 (m), 8.34–8.41
0.043 mmol) in CH Cl (10 ml) were stirred for 3 h at
2
SnH
3
2
1
3
1
1
(
m, C H N). C{ H} NMR: dC )9.4 ( J119
¼ 359
ambient temperature. The resulting solution was filtered
through a glass frit, then concentrated to ca. 2 ml. Ad-
dition of pentane caused precipitation of a light yellow
solid, which was dried in vacuo (0.042 g, 93%). Anal.
Calc. for C90H76F12N4O12P4Pd2S4 ꢀ 2H2O: C, 50.64; H,
3.78. Found: C, 50.31; H, 3.89%. LRMS in FAB mode,
m=z (relative intensity calculated, observed) for
5
4
SnC
1
Hz, J
1
1
117SnC
¼ 343 Hz, CH3), 131.5 (JSnC ¼ 27 Hz, CH),
1
48.8 (JSnC ¼ 34 Hz, CH), 153.1 ( J119
¼ 404 Hz,
SnC
J
117
¼ 386 Hz, ipso C).
SnC
2
.3. Preparation of 1,3-di(3-pyridyl)benzene (1)
PdCl (PPh ) ] (0.23 g, 0.33 mmol) and LiCl (1.4 g, 33
mmol) were added to a toluene solution (60 ml) of 3-
þ
þ
C H S O P N F Pd (M–OTf ): 1945 (41, 45), 1946
89 76 3 9 4 4 9
2
[
2
3 2
(63, 64), 1947 (81, 82), 1948 (87, 87), 1949 (100, 100),