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P. Di6ersi et al. / Journal of Organometallic Chemistry 593–594 (2000) 154–160
standard techniques. The solvents were dried and dis-
tilled prior to use. The compounds [Ir(Me)2Cp*(L)]
(L=PMe3 (1a) [1b], PMe2Ph (1b) [1c], PMePh2 (1c)
[1c], PPh3 (1d) [1b]), were prepared according to litera-
ture procedures. Commercial reagents, AgBF4,
[FeCp2]PF6, Ph3SiH, PhMe2SiH and Ph2MeSiH were
3.2.1. Complex 2a
Anal. Found: C, 55.2; H, 5.7. C31H39FIrPSi Calc.: C,
54.6; H, 5.8%; 1H-NMR (CD2Cl2): l 1.32 (9H, d,
JHP=9.9 Hz, PMe3), 1.57 (15H, d, JHP=1.8 Hz,
C5Me5), 6.9–7.7 (15H, bm, Ph); (C6D6): l 1.11 (9H, d,
PMe3), 1.47 (15H, d, C5Me5), 6.7–7.4 (bm, Ph). 13C-
NMR (C6D6): 9.81 (s, C5Me5), 18.41 (d, JCP=38 Hz,
PMe3), 97.32 (s, C5Me5), 122.5, 127.4, 127.5, 127.6,
127.7, 128.6, 135.1, 135.3, 144.6 (d, JCP=3.7 Hz) (Ph).
19F-NMR (C6D6): l −151.12 (d, JSiF=316 Hz).
used as supplied. H, 13C, 31P, 19F, H-NMR spectra
were recorded on Varian Gemini 200 and VXR 300
instruments. Elemental analyses were performed by
the Laboratorio di Microanalisi of the Istituto di
Chimica Organica, Facolta` di Farmacia, University of
Pisa.
1
2
3.2.2. Complex 2b
Anal. Found: C, 57.8; H, 5.4. C31H39FIrPSi Calc.: C,
58.1; H, 5.5%; 1H-NMR (CD2Cl2): l 1.23 (3H, d,
3.1. Reaction of dimethylphenylsilane in the presence of
1a or 1b and [FeCp2]PF6 or AgBF4: general procedure
JHP=10.1 Hz, PMe), 1.42 (3H, d, JHP=9.7 Hz, PMe),
1.48 (15H, d, JHP=1.9 Hz, C5Me5), 6.8–7.7 (bm, Ph);
(C6D6): l 1.17 (3H, d, PMe), 1.26 (3H, d, PMe), 1.40
(15H, d, C5Me5), 7.0–8.0 (bm, Ph). 19F-NMR (C6D6): l
−148.9 (d, JSiF=312 Hz).
The reaction of Ph2MeSiH in the presence of 1a and
[FeCp2]PF6 is reported as an example. Ph2MeSiH (1 ml,
6.3 mmol), 1a (6.8 mg, 0.016 mmol) and [FeCp2]PF6
(13.0 mg, 0.039 mmol) were introduced under argon
atmosphere in a two-necked flask equipped with a
reflux condenser and a stirbar, and 1.6 ml of anhydrous
deoxygenated CH2Cl2 were added. The reaction mix-
ture was heated for the desired time at constant temper-
ature, then, after removal of the volatiles, the residue
was eluted through a column of alumina by using a
benzene/pentane mixture. The oily residue was exam-
ined by 1H-NMR spectroscopy. (Me2PhSi)2 [14] and
Ph2MeSiH were identified on the basis of spectroscopic
data.
3.2.3. Complex 2c
Anal. Found: C, 60.9; H, 5.5. C41H43FIrPSi Calc.: C,
61.1; H, 5.4%. 1H-NMR (CD2Cl2): l 1.05 (3H, d,
J
HP=10.1 Hz, PMe), 1.46 (15H, d, JHP=1.7 Hz,
C5Me5), 6.8–7.7 (bm, Ph). 19F-NMR (C6D6): l −145.7
(d, JSiF=308.5 Hz).
3.2.4. Complex 2d
Anal. Found: C, 64.0; H, 5.3. C46H45FIrPSi Calc.: C,
63.6; H, 5.2%. 1H-NMR (CD2Cl2): l 1.45 (15H, d,
J
HP=2.0 Hz, C5Me5), 6.8–7.0 (bm, Ph). 19F-NMR
(Me2PhSi)2: 1H-NMR (CDCl3): l=0.32 (12H, s,
SiMe); 7.25–7.60 (10H, m, Ph) (Ref. [14] l=0.32).
(C6D6): l=0.31 (12H, s, SiMe); 7.20 (12H, m, Ph), 7.55
(8H, m, Ph). MS: m/z 270 (M+), 135.
(C6D6): l −142.3 (d, JSiF=305.4 Hz). 13C-NMR
(C6D6): 9.75 (s, C5Me5), 100.00 (s, C5Me5), 121.01–
145.39 (m, Ph).
1
Ph2MeSiH: H-NMR (CDCl3): l=0.63 (3H, d, J=
3.3. Crystallographic studies
3.7 Hz, SiMe); 4.95 (1H, q, J=3.9 Hz, SiH); 7.25–7.60
(10H, m, Ph). (CD2Cl2): 0.68 (3H, d, SiMe); 4.97 (1H,
q, SiH); 7.35–7.70 (10H, m, Ph).
Single crystals of 2a are colorless prisms. One of
them was mounted in nitrogen atmosphere on a
Siemens P4 diffractometer. Details about the crystal
parameters and intensity data collection are summa-
rized in Table 3. The diffraction symmetry and system-
atic absences suggested the Cc or C2/c as possible space
groups. The first was chosen on the basis of the cell
volume and the possible symmetry elements of the
molecule. The collected data were corrected for
Lorentz, polarization and absorption effects by means
of a C-scan method [15]. The structure solution was
obtained by means of direct methods by using the
TREF procedure contained in SHELXTL package [16].
Some degree of disorder in molecule conformation is
revealed by abnormally high values of some thermal
factors and by the inconsistent geometry of some rings.
The refinement was performed by constraining the
phenyl ring C(11)\C(16) and the pentamethylcy-
clopentadienyl ring C(1)\C(5) to have an ideal geome-
3.2. General procedure for the reaction of
[Ir(Me)2Cp*L] (1a–d) with SiPh3H and [FeCp2]PF6:
formation of [Ir(Ph)(SiPh2F)Cp*L] (2a–d)
Complexes 1a–d (20–30 mg), ferrocenium hex-
afluorophosphate (equimolar amounts) and triphenylsi-
lane (Si:Ir molar ratio=2) were reacted in CH2Cl2
(0.75 ml) under stirring. A vigorous formation of
methane was observed (l 0.20 ppm in CD2Cl2). Fer-
rocene was formed (l 4.18 ppm in CD2Cl2). After 1–2
h the reaction mixture was dried under vacuum. The
yellow oily residue was chromatographed on an alu-
mina column by eluting with pentane/benzene. The
eluted product was crystallized from dichloromethane/
pentane to give 2a (83%), 2b (81%), 2c (75%), 2d (70%)
as white crystals.