V. De Felice et al. / Journal of Organometallic Chemistry 692 (2007) 5211–5220
5217
performed on a Crison Conductimeter, model microCM
2200. The complexes [PtCl2(1,5-COD)] [18], [PtCl(CH3)-
(1,5-COD)] [18], [Pt(CH3)2(1,5-COD)] [18], [PdCl(CH3)-
(1,5-COD)] [19] and [PdCl2(1,5-COD)] [20] were obtained
by known methods.
Anal. Calc. for C44H48P4Pt2: C, 48.45; H, 4.44. Found:
C, 48.21; H, 4.56%.
1H NMR relevant resonances (CD2Cl2) d: 3.2 (br, 2H,
2
CH2P); 2.5 (br, 2H, CH2P); 0.45 (m, 6H, JPt–H = 74);
31P NMR resonance (CD2Cl2) d = 13.57 (s, 1JPt–P = 1925).
Particular care was employed in excluding moisture or
air in the synthesis of bedip, which was obtained as previ-
ously reported [11].
4.3. Synthesis of [PdCl(CH3)(l-bedip)]2 (1e)
Two alternative procedures were used to prepare 1e:
4.1. Synthesis of [PtX(CH3)(l-bedip)]2 (X = Cl, Br, I)
(1a-c)
(a) A solution of bedip (48 mg, 0.15 mmol) in dichloro-
methane (1 mL) was added to a stirred solution of
[PdCl(CH3)(1,5-COD)] (40 mg, 0.15 mmol) in the
same solvent (2 mL). After 2 h the orange solution
was passed on a small Celite bed and concentrated
to a small volume. Addition of diethyl ether
prompted the precipitation of the yellow product.
Yield: 85%.
(b) A solution of bedip (48 mg, 0.15 mmol) in dichloro-
methane (1 mL) was added to a stirred solution of
[PdCl2(1,5-COD)] (43 mg, 0.15 mmol) in the same
solvent (2 mL). After 24 h the yellow solid was recov-
ered by filtration, suspended in dichloromethane
(1 mL) and Sn(CH3)4 (25 mg, 0.14 mmol) was added.
After 24 h of stirring the resulting orange solution
was passed on a small Celite bed and concentrated
to a small volume. Addition of diethyl ether
prompted the precipitation of the yellow product.
Yield: 75%.
A solution of bedip (36 mg, 0.11 mmol) in chloroform
(1 mL) of was added to a stirred solution of [PtX(CH3)-
(1,5-COD)] (0.11 mmol) in the same solvent (1 mL). After
1 h, the solution was passed on a small Celite bed and
the solvent was removed in vacuo. The crude product
was dissolved in a minimum amount of chloroform and
diethyl ether was added to crystallize the product as a yel-
low (X = Cl, Br) or yellow-orange (X = I) microcrystalline
solid. The solid was washed with diethyl ether and dried in
vacuo. Yield: 85–90%.
Compound 1a: Anal. Calc. for C42H42Cl2P4Pt2: C, 44.58;
H, 3.74. Found: C, 44.28; H, 3.60%.
1H NMR relevant resonances (CD2Cl2) d: (M isomer)
4.2 (br, 2H, CH2P); 2.6 (br, 2H, CH2P); ꢀ0.45 (m, 3H,
2JPt–H = 61); (m isomer) 3.4 (br, 2H, CH2P); 2.0 (br, 2H,
3
3
CH2P); 0.98 (t, 3H, JP–H = 7.2); ꢀ0.30 (t, 3H, JP–H
=
=
7.2); 31P NMR resonance (CD2Cl2) d = 5.75 (s, JPt–P
1
3174).
Compound 1b: Anal. Calc. for C42H42Br2P4Pt2: C, 41.33;
H, 3.47. Found: C, 41.52; H, 3.37%.
Anal. Calc. for C42H42Cl2P4Pd2: C, 52.86; H, 4.44.
Found: C, 52.60; H, 4.37%.
1H NMR relevant resonances (CD2Cl2) d: (M isomer)
4.3 (br, 2H, CH2P); 2.8 (br, 2H, CH2P); ꢀ0.45 (m, 3H,
2JPt–H = 80); (m isomer) 3.4 (br, 2H, CH2P); 2.4 (br, 2H,
1H NMR relevant resonances (CD2Cl2) d: (M isomer)
4.15 (br, 2H, CH2P); 2.5 (br, 2H, CH2P); ꢀ0.40 (m, 3H);
3
3
(m isomer) 1.04 (t, 3H, JP–H = 4.9); ꢀ0.16 (t, 3H, JP–H
=
3
3
CH2P); 1.18 (t, 3H, JP–H = 6.0); ꢀ0.22 (t, 3H, JP–H
=
=
4.9); (mm isomer) 0.43 (m, 3H); 31P NMR resonance
(CD2Cl2) d = 12.4 (s).
1
6.0); 31P NMR resonance (CD2Cl2) d = 7.7 (s, JPt–P
3098).
Compound 1c: Anal. Calc. for C42H42I2P4Pt2: C, 38.38;
H, 3.22. Found: C, 38.45; H, 3.60%.
4.4. Synthesis of [Pt(CH3)(PPh3)(bedip)]BF4 (2)
1H NMR relevant resonances (CD2Cl2) d: (M isomer)
4.4 (br, 2H, CH2P); 2.9 (br, 2H, CH2P); ꢀ0.45 (m, 3H,
2JPt–H = 77); (m isomer) 3.5 (br, 2H, CH2P); 1.12 (t, 3H,
To a stirred solution of [PtCl(CH3)(l-bedip)]2 (96 mg,
0.085 mmol) in a minimum amount of a dichlorometh-
ane/nitromethane (1:1), a solution of AgBF4 (33 mg,
0.17 mmol) and PPh3 (44 mg, 0.17 mmol) in nitromethane
(0.5 mL) was added and the stirring was continued for
24 h at r.t. The solvent was removed in vacuo and the
residue was extracted with chloroform (3 · 1 mL). The
solution was concentrated to a small volume and passed
on a small Celite bed. Addition of diethyl ether prompted
the precipitation of the white product. Yield: 80%.
Anal. Calc. for C39H36BF4P3Pt: C, 53.26; H, 4.13.
Found: C, 53.15; H, 4.51%.
3
3JP–H = 6.7); ꢀ0.15 (t, 3H, JP–H = 6.7); 31P NMR reso-
1
nance (CD2Cl2) d = 5.4 (s, JPt–P = 3057).
4.2. Synthesis of [Pt(CH3)2 (l-bedip)]2 (1d)
A solution of bedip (58 mg, 0.18 mmol) in tetrahydrofu-
ran (1 mL) was added to a stirred solution of [Pt(CH3)2-
(1,5-COD)] (60 mg, 0.18 mmol) in the same solvent
(1 mL). After 2.5 h the yellow solution was passed on a
small Celite bed and the solvent was removed in vacuo.
The crude product was dissolved in a minimum amount
of tetrahydrofuran and diethyl ether was added to crystal-
lize the product as a white solid. The solid was washed with
diethyl ether and dried in vacuo. Yield: 75%.
1H NMR relevant resonances (CD3NO2) d: 3.3 (br, 2H,
2
CH2P); 2.4 (br, 2H, CH2P); 0.44 (app q, 3H, JPt–H = 65,
3JP–H = 6.7); 31P NMR resonances (CD3NO2) d = 33.2
1
2
1
(d, JPt–P = 2948, JP–P(trans) = 389); 45.2 (s, JPt–P
=
1
2106); 49.6 (d, JPt–P = 2592).