72
M. Caporali et al. / Journal of Organometallic Chemistry 714 (2012) 67e73
Fig. 4. Eyring plot for the hydrolysis of 2 in DMF.
reaction mixture changed from pale-yellow to orange. The solvent
was evaporated to dryness and the orange-red residue was washed
with diethyl ether (2 ꢃ 3 mL) before being dried under vacuum. The
solvent was evaporated to dryness and the residue was then dis-
solved in dry DMF in order to remove AgCl. After filtration through
cannula the solvent was evaporated from the filtrate and the
product was dried in vacuum. Yield 26.2 mg, 74%. Anal. Calcd for 2b,
C41H33BF4Na2O6P6RuS2 (Mw ¼ 1105.52): C 44.54, H 3.01, P 16.81, S
5.80. Found: C 44.25, H 3.18, P 16.69, S 5.79.
(molecular peak), 848.9 (Mꢀ/z ꢀ PH3) (fragment derived from loss
of PH3).
4.1.5. Synthesis of [CpRu(TPPMS)2{P(OH)3}]PF6 (4)
[CpRu(TPPMS)2Cl] (15.0 mg, 0.0161 mmol, 1.0 equiv) was dis-
solved in 0.5 mL of DMF, TlPF6 (5.6 mg, 0.0161 mmol, 1.0 equiv) and
H3PO3 (1.32 mg, 1.0 equiv) were added. After 3 h at RT, the white
fine microcrystalline precipitate of TlCl separated out from the
solution and the surnatant was taken off by syringe. The solvent
was evaporated to dryness and the residue was dissolved in DMF-
d7, for NMR characterization.
The complexes 2a and 2b exhibit identical NMR spectra
excepting the signals of the counter ion PFꢀ6 in 2a.
1H NMR (300.13 MHz, CD3OD, 20 ꢁC):
d
¼ 4.8 (Cp, s, 5 H), 7.0e7.5
4.1.3. Synthesis of [CpRu(TPPMS)2(PH3)]PF6 (3a)
(m, 24 H, aromatic), 8.0e8.2 (m, 4 H, aromatic).
To a solution of [CpRu(TPPMS)2(
mmol, 1.0 equiv) in DMF, degassed water (28.0
h
1-P4)]PF6 (200.0 mg, 0.172
L, 1.556 mmol,
31P{1H} NMR (121.49 MHz, CD3OD, 20 ꢁC):
d
¼ 131.1 (t,
m
2JPP ¼ 63.9 Hz, 1P, P(OH)3), 46.2 (d, 2JPP ¼ 63.9 Hz, 2P, TPPMS), ꢀ143.5
(septet,1JPF ¼ 709.6 Hz,1P, PF6). The proton-coupled 31PNMRspectrum
shows invariant signals, confirming the absence of any PeH bonds.
10.0 equiv) was added and the resulting mixture was stirred for
12 h at RT. Addition of diethyl ether caused the precipitation of the
product that was separated by filtration with cannula. The yellow
solid was washed with diethyl ether (2 ꢃ 5 mL) before being dried
under vacuum. Yield: 88.1 mg, 48%. Anal. Calcd for 3a,
C41H36F6Na2O6P4RuS2 (Mw ¼ 1073.79): C 45.86, H 3.38, P 11.54, S
5.97. Found: C 45.52, H 3.48, P 11.20, S 5.79.
4.2. Kinetic study
4.2.1. Kinetic measurements for the hydrolysis of 2a
Degassed water (2.0 mL, 0.111 mmol, 10 equiv) was added to an
1H NMR (300.13 MHz, DMF-d7, 20 ꢁC):
d
¼ 5.1 (dt,
NMR Evans tube (C6D6) containing 12.9 mg (0.011 mmol,1 equiv) of
complex 2a dissolved in 0.45 mL of DMF. The resulting solution was
monitored by 31P NMR spectroscopy until complete disappearance
of 2a. The main products formed during hydrolysis exhibited
resonances assigned to H3PO3, H3PO4 and [CpRu(TPPMS)2(PH3)]PF6
(3a). The relative concentration of each species in the reaction
mixture was determined by integration of the corresponding
signals in the 31P{1H} NMR spectra, referenced to a known amount
of PPh3 dissolved in C6D6 and used as an internal reference.
Activation parameters were extracted by ln k/T vs. 1/T plot
according to equation (1).
1JPH ¼ 358.7 Hz, 3JPH ¼ 5.5 Hz, 3H, PH3), 5.5 (s, 5H, Cp), 7.5e7.7 (m, 6
H, aromatic), 7.9e8.2 (m, 20 H, aromatic), 8.5 (m, 2H, aromatic). 31P
{1H} NMR (121.49 MHz, DMF-d7, 20 ꢁC):
d
¼ 45.1 (d, JPP ¼ 51.0 Hz,
2
2
2P, TPPMS), ꢀ112.9 (t, JPP ¼ 51.0 Hz, 1P, PH3), ꢀ143.6 (septet,
1JPF ¼ 709.6 Hz, PF6); 31P NMR (121.49 MHz, DMF-d7, 20 ꢁC):
d
¼ 45.1 (br d, 2JPP ¼ 51.0 Hz, 2P, TPPMS), ꢀ112.9 (qt, 1JPH ¼ 358.7 Hz,
2JPP ¼ 51.0 Hz,1P, PH3), ꢀ143.6 (septet, 1JPF ¼ 709.6 Hz, PF6); ESI-MS:
C41H36O6P3RuS2 (mass of the complex anion, without 2 Naþ), Mꢀ/z:
883.0 (molecular peak), 848.9 (Mꢀ/z ꢀ PH3) (fragment derived from
loss of PH3).
ꢀ ꢁ
Hs
D
Ss
R
4.1.4. Synthesis of [CpRu(TPPMS)2(PH3)]BF4 (3b)
k
T
D
R$T
ln
¼ ꢀ
þ
þ lnðKb=hÞ
(1)
Complex [CpRu(TPPMS)2(PH3)]BF4 was prepared from
[CpRu(TPPMS)2(h
1-P4)]BF4 following a procedure similar to that of
3a. Yield: 86.8 mg, 50%. Anal. Calcd for 3b, C41H36BF4Na2O6P3RuS2
(Mw ¼ 1015.63): C 48.49, H 3.57, P 9.15, S 6.31. Found: C 48.34, H
3.68, P 9.08, S 6.22.
Acknowledgements
The complex cations of 3a and 3b exhibit identical NMR and IR
spectra apart for the counter anions. ESI-MS: C41H36O6P3RuS2
(mass of the complex anion, without
This work was financially supported by the Russian Foundation
for Basic Research (Project No. 09-03-00933-a), the Italian National
Research Council and the Russian Academy of Sciences (CNR/RAS
2
Naþ), Mꢀ/z: 883.0