2574 Organometallics, Vol. 28, No. 8, 2009
Zhao et al.
CD2Cl2, 25 °C): δ 13.13 (s, satellites; JPt-H ) 61.0 Hz; 1H,
δ 13.07 (s, satellites; JPt-H ) 56.9 Hz; 1H, CHSnPh3), 8.74 (dd; 3J
) 5.5 Hz, 4J ) 1.0 Hz; 2H, 7-aza), 7.90 (dd; 3J ) 7.5 Hz, 4J ) 1.0
Hz; 2H, 7-aza), 7.74 (m, satellites; 3JSn-H ) 51.0 Hz; 8H, 2H from
7-aza and 6H from SnPh3), 7.50 (m; 3H, SnPh3), 7.45 (m; 6H,
SnPh3), 7.21 (m, satellites; 3JPt-H ) 68.4 Hz; 4H, PtPh2), 6.99 (dd;
3J1 ) 5.5 Hz, 3J2 ) 7.5 Hz; 2H, 7-aza), 6.65 (m; 6H, PtPh2) ppm.
13C NMR: δ 147.61, 142.25, 138.48, 137.69, 136.05, 133.98,
130.58, 130.50, 130.11, 126.54, 124.37, 121.56, 117.34, 103.10,
66.51 ppm. 119Sn NMR (186 Hz, CD2Cl2, 25 °C): δ 0.75 ppm. Anal.
Calcd for C45H36N4PtSn · CH2Cl2: C, 53.56; H, 3.71; N, 5.43. Found:
C, 53.59; H, 3.86; N, 4.86.
3
CHSiMe3), 8.72 (d; J ) 5.5; 2H, 7-aza), 7.96 (d;3J ) 8.0; 2H,
7-aza), 7.56 (d;3J ) 3.5; 2H, 7-aza), 7.04 (dd; 3J1 ) 5.5 Hz, 3J2 )
8.0 Hz; 2H, 7-aza), 6.59 (d;3J ) 3.5 Hz; 2H, 7-aza), 0.67 (s,
2
satellites; JPt-H ) 88.0 Hz; 6H, PtMe2) 0.45 (s; 9H, CHSiMe3)
ppm. 13C NMR: δ 146.51, 144.89, 129.25, 127.88, 123.24, 117.40,
102.21, 54.69, -1.79, -19.85 (1JPt-H ) 838.6 Hz; PtMe2) ppm.
Anal. Calcd for C20H26N4PtSi: C, 44.03; H, 4.80; N, 10.27. Found:
C, 44.37; H, 4.79; N, 9.88.
Synthesis of Pt(Me3Si-BAM)Ph2 (3). Ligand 1a (0.032 g, 0.10
mmol) and [PtPh2(µ-SMe2)]n (n ) 2, 3) (0.041 g, 0.10 mmol based
on Pt) were mixed in THF (10 mL), and the mixture was stirred
overnight at room temperature. The solvent was evaporated, and
the resulting white solid was then washed with Et2O (3 mL × 3)
to afford 3 as a white powder (0.056 g, 84% yield). 1H NMR (400
Hz, CD2Cl2, 25 °C): δ 12.60 (s, satellites; JPt-H ) 44.1 Hz; 1H,
Alternatively, allowing the solution of Ph3Sn-BAM (1c) (16 mg,
0.026 mmol) and [PtMe2(µ-SMe2)]2 (15 mg, 0.026 mmol) in CH2Cl2
(0.8 mL) to stand at room temperature in the dark resulted in
colorless crystals of 7 (∼6 mg, 24% yield based on 1c).
Reactivity Study of Pt(Me3Si-BAM)Me2 (2) with MeOTf. An
1H NMR spectrum was first recorded for a dry CD2Cl2 (0.40 mL)
(CD2Cl2 was dried with CaH2 prior to use) solution of 2 (∼8 mg).
MeOTf (1.7 µL, ∼1.05 equiv) was then added via micropipet at
room temperature. The NMR tube was shaken vigorously for a few
seconds, and then a new NMR spectrum of the solution was
recorded. The 1H NMR data indicated the clean formation of
[Pt(Me3Si-BAM)Me3](OTf) (8). 1H NMR (500 Hz, CD2Cl2, 25 °C):
3
4
CHSiPh3), 8.75 (dd; J ) 5.5 Hz, J ) 1.2 Hz; 2H, 7-aza), 7.90
3
4
3
(dd; J ) 8.0 Hz, J ) 1.2 Hz; 2H, 7-aza), 7.65 (d; J ) 4.0 Hz;
2H, 7-aza), 7.41 (m, satellites; JPt-H ) 74.6 Hz; 4H, Ph), 6.98
3
3
3
(dd; J1 ) 5.5 Hz, J2 ) 8.0 Hz; 2H, 7-aza), 6.80 (m; 4H, Ph),
6.70 (m; 2H, Ph), 6.61 (d;3J ) 4.0 Hz; 2H, 7-aza) ppm. 13C NMR:
δ 146.37, 145.18, 142.56, 138.32, 130.23, 128.17, 126.52, 123.89,
121.68, 117.06, 102.72, 55.83, -0.95 ppm. Anal. Calcd for
C30H30N4PtSi: C, 53.80; H, 4.51; N, 8.37. Found: C, 53.64; H, 4.73;
N, 8.30.
3
3
δ 8.41 (d; J ) 5.0 Hz; 2H, 7-aza), 8.20 (d; J ) 8.0 Hz; 2H,
7-aza), 7.65 (d; 3J ) 4.0 Hz; 2H, 7-aza), 7.40 (dd; 3J1 ) 5.0 Hz,3J2
) 8.0 Hz; 2H, 7-aza), 6.95 (d; J ) 4.0 Hz; 2H, 7-aza), 5.00 (s,
3
Synthesis of Pt(N,C,N-BAM)(SnMe3)Me2 (4). 1b (0.041 g, 0.10
mmol) and [PtMe2(µ-SMe2)] (0.057 g, 0.10 mmol) were mixed in
dry CH2Cl2 (10 mL), and the mixture was stirred for 1 day at room
temperature. After the solvent was decanted, the residue was purified
by flash chromatography on silica gel using CH2Cl2/hexanes (1:1)
as the eluent to afford 4 as a colorless oil in >90% yield. 1H NMR
satellites; JPt-H ) 88.9 Hz; 1H, bridging CH’(SiMe3)), 1.79 (s,
satellites; 2JPt-H ) 73.5 Hz; 9H, Pt-Me), 0.55 (s; 9H, SiMe3) ppm.
13C NMR: δ 148.14, 142.09, 133.23, 127.97, 124.96, 118.92,
105.86, 65.89, -0.98, -6.53 (1JPt-H ) 629 Hz; Pt-Me) ppm.
Complex 8 decomposed completely after 3 days, resulting in the
tetrameric complex [PtMe3(OTf)]4 via extrusion of ligand 1a.
3
(400 Hz, CD2Cl2, 25 °C): δ 8.32 (dd, satellites; J ) 5.6 Hz; 1H,
3
4
1
7-aza), 8.25 (dd; J ) 5.2 Hz, J ) 1.2 Hz; 1H, 7-aza), 7.90 (m;
Reactivity Study of Pt(Me3Si-BAM)Me2 (2) with I2. An H
2H, 7-aza), 7.58 (d; 3J ) 3.2 Hz; 1H, 7-aza), 7.53 (d; 3J ) 3.2 Hz;
1H, 7-aza), 7.08-7.01 (m; 2H, 7-aza), 6.76 (d; J ) 3.2 Hz; 1H,
NMR spectrum was first recorded for a CD2Cl2 (0.40 mL) solution
of 2 (∼8 mg). I2 (4 mg, ∼1.05 equiv) was then added at room
temperature. After being shaken vigorously to dissolve I2, the
3
3
2
7-aza), 6.73 (d; J ) 3.2 Hz; 1H, 7-aza), 5.99 (s, satellites; JPt-H
) 16.4 Hz; 1H, bridging CH), 0.73 (s, satellites; 2JPt-H ) 42.4 Hz;
3H, Pt-Me), 0.52 (s, satellites; 2JPt-H ) 64.4 Hz; 3H, Pt-Me), -0.25
(s, satellites; 2JSn-H ) 48.0 Hz, 3JPt-H ) 10.0 Hz; 9H, Pt-SnMe3)
ppm. 13C NMR (100 Hz, CD2Cl2, 25 °C): δ 154.76, 152.43, 139.28,
137.46, 129.96, 129.82, 129.21, 128.29, 119.70, 119.14, 115.91,
1
solution was monitored regularly by H NMR over several days.
The products generated were identified to be a mixture containing
Pt(Me3Si-BAM)(I)2 (9), MeI (1H, δ ) 2.20 ppm), free ligand 1a,
2
and [PtMe3I]4 (1H, δ ) 1.73 ppm, JPt-H ) 77.2 Hz). Slow
evaporation of the CD2Cl2 solution afforded yellow crystals, which
were characterized by single-crystal X-ray diffraction analysis to
be the co-crystallized product of complex 9 with [PtMe3I]4. 1H NMR
(500 Hz, CD2Cl2, 25 °C) of 9: δ 12.89 (s, satellites; JPt-H ) 50.0
Hz; 1H, CHSiMe3), 9.01 (d; 3J ) 6.5 Hz; 2H, 7-aza) 8.00 (d; 3J )
7.0 Hz; 2H, 7-aza), 7.64 (d; 3J ) 2.0 Hz; 2H, 7-aza), 7.16 (dd; 3J1
1
104.09, 103.48, 72.80 (s, satellites; JPt-C ) 483.7 Hz; bridging
1
CH’-Pt), -8.33 (s, satellites; JPt-C ) 459.6 Hz, Pt-Me), -11.89
(s, satellites; 1JSn-C ) 65.6 Hz, SnMe3), -21.64 (s, satellites; 1JPt-C
) 316.3 Hz, Pt-Me) ppm. 119Sn NMR (186 Hz, CD2Cl2, 25 °C): δ
-84.42 (2JPt-Sn
) 10728.7 Hz) ppm. HRMS: calcd for
[C20H26N4PtSn + H+] 637.0885, found 637.0805.
3
3
) 6.5 Hz, J2 ) 7.0 Hz; 2H, 7-aza), 6.71 (d; J ) 2.0 Hz; 2H,
7-aza) ppm. The reaction of 2 (∼8 mg) with 3 equiv of I2 (∼11
mg) in CD2Cl2 (0.40 mL) at room temperature gave similar results,
again producing 9, MeI, free ligand 1a, and [PtMe3I]4. Slow
evaporation of the CD2Cl2 solution afforded deep red crystals, which
were characterized by single-crystal X-ray diffraction analysis to
be the co-crystallized product of 9 with I2. The X-ray data for the
co-crystallized product of 9 with I2 are provided in the Supporting
Information.
In Situ Syntheses of Pt(Me3Sn-BAM)Ph2 (5) and
Pt(N,C,N-BAM)(SnMe3)Ph2 (6). An NMR tube was charged with
Me3Sn-BAM (2) (8.3 mg, 0.020 mmol) and [PtPh2(µ-SMe2)]n (n
) 2, 3) (16.6 mg, 0.040 mmol based on Pt). CD2Cl2 (0.50 mL)
was added via syringe at room temperature. The NMR tube was
shaken to dissolve the solid, and the 1H NMR spectra were
monitored over two months. Diagnostic 1H NMR (500 Hz, CD2Cl2,
2
25 °C) of 5: δ 12.67 (s, satellites; JSn-H ) 55.1 Hz, JPt-H ) 34.9
3
4
Hz; 1H, bridging CH), 8.75 (dd, satellites; J ) 5.0 Hz, J ) 1.0
Reactivity Study of Pt(N,C,N-BAM)(SnMe3)Me2 (4) with
I2. In a typical experiment, an 1H NMR spectrum was first recorded
for a dry CD2Cl2 (0.45 mL) solution of 4 (13 mg). I2 (1∼2 mg,
0.2-0.4 equiv) was added at room temperature. After being shaken
vigorously to dissolve I2, the solution was monitored by 1H or 119Sn
NMR spectroscopy after several minutes. I2 was added repeatedly
to reach a total amount of ∼4 equiv. With I2 < 1.0 equiv, the
products were identified to be a mixture containing MeI (1H, δ )
2.20 ppm), Me3SnI (119Sn, δ ) 47.6 ppm), Pt(N,C,N-BAM-
)Me(I)(SnMe3) (10) (12% yield), Pt(I-BAM)Me2(I)(SnMe3) (11)
(60% yield), and Pt(N,C,N-BAM)PtMe2(I) (12a) (28% yield). Note:
The yields of these resulting Pt(IV) species were calculated
3
1
Hz, JPt-H ) 21.6 Hz; 2H, 7-aza). Diagnostic H NMR (500 Hz,
CD2Cl2, 25 °C) of 6: 6.33 (s, satellites; 2JPt-H ) 14. Hz; 1H, bridging
CH), -0.30 (s, satellites; JSn-H ) 48.4 Hz,3JPt-H ) 9.0 Hz; 9H,
2
SnMe3) ppm.
Synthesis of Pt(Ph3Sn-BAM)Ph2 (7). Ph3Sn-BAM (1c) (0.030
g, 0.05 mmol) and [PtPh2(µ-SMe2)]n (n ) 2, 3) (0.040 g, 0.10 mmol
based on Pt) were mixed in in CH2Cl2 (4 mL), and the mixture
was stirred overnight at room temperature. The solvent was
evaporated, and the resulting white solid was then recrystallized
with CH2Cl2/hexanes (1:2) mixed solution to afford 7 as a white
1
powder (0.036 g, 77% yield). H NMR (500 Hz, CD2Cl2, 25 °C):