44
S. Paa6ola et al. / Journal of Organometallic Chemistry 645 (2002) 39–46
4.4. Synthesis of 5 (method B)
with KBr pellets on a Shimadzu FTIR-8300 spec-
trophotometer. 1H-NMR (300.13 MHz), 13C{1H}-
NMR (75.47 MHz), 31P{1H}-NMR (121.48 MHz) and
11B-NMR (96.29 MHz) spectra were recorded with a
Bruker ARX 300 instrument equipped with the appro-
priate decoupling accessories. Chemical shift values for
11B-NMR spectra were referenced to external BF3·OEt2
and those for 1H- and 13C{1H}-NMR spectra were
referenced to SiMe4. Chemical shift values for 31P{1H}-
NMR spectra were referenced to external 85% H3PO4.
Chemical shifts are reported in units of parts per mil-
lion (ppm) downfield from Me4Si, and all coupling
constants are reported in Hz.
Tetramethyltin (0.03 ml, 0.21 mmol) was added drop-
wise to a solution of 3 (0.11 g, 0.16 mmol) in CH2Cl2
(10 ml). The mixture was refluxed for 20 h and filtered
through Celite, and the solvent was evaporated in
vacuo. The obtained solid was washed with cold Et2O
and dried in vacuo (0.089 g, 81%). Characterisation was
as for method A.
4.5. Synthesis of 6 (method A)
A mixture of 2 (0.20 g, 0.53 mmol) and [PdClMe-
(cod)] (0.14 g, 0.53 mmol) in CH2Cl2 (15 ml) was
refluxed for 20 h. The mixture was filtered through
Celite and the filtrate was dried in vacuo. The obtained
solid was washed with cold Et2O and dried in vacuo
(0.24 g, 86%). Anal. Calc. for C15H41B10ClP2Pd: C,
33.77; H, 7.75. Found: C, 33.55; H, 7.46%. IR: w
(cm−1)=3004, 2969, 2933, 2905, 2889 (CꢀH); 2657,
2636, 2627, 2616, 2586 (BꢀH); 1460, 1385, 1369, 1139,
4.2. Materials
Unless otherwise noted, all manipulations were car-
ried out under an argon atmosphere using standard
vacuum line techniques. Diethyl ether was distilled
from sodium benzophenone before use. Dichloro-
methane was dried over molecular sieves and deoxy-
genated prior to use. All other solvents were of reagent
grade quality and used without further purification.
[PdClMe(cod)] was prepared according to the literature
method [9]. 1,2-(PPh2)2-1,2-C2B10H10 [22], 1,2-(PiPr2)2-
1,2-C2B10H10 [1e], [PdCl2(1,2-(PPh2)2-1,2-C2B10H10)]
and [PdCl2(1,2-(PiPr2)2-1,2-C2B10H10)] [8] were synthe-
sised by published methods.
1
1072, 1036, 878, 737, 639, 503 (phosphines). H-NMR
(CD2Cl2, 25 °C): l=0.81 (dd, 3J(P,H)trans=7.50,
3J(P,H)cis=3.45, CH3, 3H); 1.47–1.73 (m, CH3, 24H);
2.75 (m, CH, 4H). 13C{1H}-NMR (CD2Cl2, 25 °C):
2
l=6.90 (d, J(C,P)trans=99.88, PdꢀCH3); 19.45, 20.02,
20.53, 21.45, 21.71, 21.82 (s, CH3); 29.83, 30.11 (CH);
86.70, 91.24 (m, Cc). 11B-NMR (CD2Cl2, 25 °C): l=
1
0.02 (3B); −3.61 (d, J(B,H)=147, 2B); −10.19 (5B).
31P{1H}-NMR (CD2Cl2, 25 °C): l=82.22 (d,
2
2J(P,P)=30.9); 104.43 (d, J(P,P)=30.9).
4.3. Synthesis of 5 (method A)
4.6. Synthesis of 6 (method B)
A mixture of 1 (0.12 g, 0.23 mmol) and [PdClMe-
(cod)] (0.06 g, 0.23 mmol) in CH2Cl2 (12 ml) was
refluxed for 20 h. The mixture was filtered through
Celite and the filtrate was dried in vacuo. The obtained
solid was washed with cold Et2O and dried in vacuo
(0.12 g, 80%). Anal. Calc. for C27H33B10ClP2Pd: C,
48.44; H, 4.97. Found: C, 48.60; H, 5.16%. IR: w
(cm−1)=3054, 2976, 2895 (CarylꢀH); 2616, 2572, 2546
(BꢀH); 1437, 1094, 745, 689, 504 (phosphines). 1H-
Tetramethyltin (0.03 ml, 0.25 mmol) was added drop-
wise to a solution of 4 (0.11 g, 0.19 mmol) in CH2Cl2
(10 ml). The mixture was refluxed for 21 h and filtered
through Celite, and the solvent was evaporated in
vacuo. The obtained solid was washed with cold Et2O
and dried in vacuo. As NMR study showed that no
reaction had occurred, the synthesis was continued with
the addition of CH2Cl2 (40 ml) and SnMe4 (0.12 ml,
1.00 mmol) to the earlier obtained ‘product’. The mix-
ture was refluxed for 10 days, filtered through Celite,
dried in vacuo, washed with Et2O, and dried in vacuo.
Characterisation was as for method A (0.037 g, 37%).
NMR (CD2Cl2, 25 °C): l=0.68 (dd, 3J(P,H)trans
=
3
8.10, J(P,H)cis=4.29, CH3, 3H); 1.50–3.35 (br, BꢀH,
10H); 7.51–7.63 (m, Haryl, 12H); 8.08–8.21 (m, Haryl
,
8H). 13C{1H}-NMR (CD2Cl2, 25 °C): l=15.41 (d,
2J(P,C)trans=101.3, CH3); 86.85 (t, 1J(C,P)=12.49,
1
1
Cc); 91.73 (d, J(C,P)=29.13, Cc); 126.5 (d, J(C,P)=
4.7. X-ray crystallographic study
1
54.10, ipso-Caryl), 128.2 (d, J(C,P)=33.29, ipso-Caryl);
129.0 (d, 3J(C,P)=9.71, m-Caryl); 132.7 (s, p-Caryl),
133.3 (s, p-Caryl); 136.2 (d, 2J(C,P)=13.87, o-Caryl),
Crystals of 5·CH2Cl2 and 6 were grown from CH2Cl2
and CH2Cl2–n-hexane, respectively. Single-crystal data
collections were performed at −80 °C on a Rigaku
AFC7S diffractometer using graphite monochromatized
Mo–Ka radiation. The unit cell parameters for both
compounds were determined by least-squares refine-
ment of 25 carefully centred reflections. A total of 6341
136.3 (d, J(C,P)=12.48, o-Caryl). 11B-NMR (CD2Cl2,
2
1
25 °C): l= −1.12 (d, J(B,H)=175, 2B), −3.46 (d,
1J(B,H)=189, 3B), −9.68 (5B). 31P{1H}-NMR
(CD2Cl2, 25 °C): l=59.16 (d, 2J(P,P)=39.6), 80.54
2
(d, J(P,P)=39.6).