S. K. Sarkar et al.
reagent grade and used as received. For spectroscopic studies
HPLC-grade solvents were used.
(C-9); 130.7 (C-10); 128.7 (C-11); 194.5 (CO); 37.0 (N―CH2―CH3);
18.5 (N―CH2―CH3); 29.0 (S―CH2―CH3); 19.3 (S―CH2―CH3);
133.0 (o,o′-C―PPh3), 130.1 (m,m′-C―PPh3) 128.2 (p-C―PPh3). UV–
Microanalytical data (C, H, N) were collected on PerkinElmer
2400 CHNS/O elemental analyzer. Infrared spectra were taken
on a RX-1 PerkinElmer spectrophotometer with samples pre-
pared as KBr pellets. UV–visible spectral studies were performed
on a PerkinElmer Lambda 25 spectrophotometer. 1H NMR spectra
were recorded using a Bruker (AC) 300 MHz FTNMR spectrometer
in CDCl3. Cyclic voltammetric measurements were carried out in
the potential range 2 V using a CH1 600(D) electrochemical
workstation. A platinum disc working electrode, a platinum wire
auxiliary electrode and Ag/AgCl reference electrode were used in
a standard three-electrode configuration. [nBu4N][ClO4] was used
as the supporting electrolyte in acetonitrile with a scan rate of 50 mV
visible (CH3CN): λmax (ε,
M
À1 cmÀ1): 489 (2723), 363 (3102),
310 (3519). For C49H45F6N4OP3RuS (2c): C, 56.27 (56.38); H, 4.34
(4.29); N, 5.36 (5.40). IR data (KBr disc) (cmÀ1): 2038 (υ(Ru―H)),
1941 (υ(CO)), 1573 (υ(C=H;N), 1378 (υ(N=H;N)), 843 (υ(PFÀ6 )). 1H
NMR data in CDCl3 (δ, ppm): 6.97, 7.18 (imidazolyl-2H), 7.82 (o-H,
d, 7.0Hz), 7.58 (m-2H), 7.28 (o′-H) (C6H4S―Me, aromatic H’s), 4.21
(N―CH2―CH3, q, J =7.5Hz), 1.42 (N―CH2―CH3, t, J = 7.5 Hz), 2.73
(S―CH3, s), À10.05 (Ru―H, t, J = 20.5 Hz). 13C NMR data (CDCl3,
ppm): 154.0 (C-2); 129.2 (C-4); 130.9 (C-5); 154.8 (C-6); 136.1 (C-7);
133.1 (C-8); 130.8 (C-9); 130.4 (C-10); 128.3 (C-11); 200.0 (CO);
39.0 (N―CH2―CH3); 19.8 (N―CH2―CH3); 17.0 (S―CH3); 132.8 (o,
o′-C―PPh3), 129.6 (m,m′-C―PPh3) 127.9 (p-C―PPh3). UV–visible
(CH3CN): λmax (ε, MÀ1 cmÀ1): 485 (2314), 359 (2942), 311 (2783). For
C49H45F6N4OP3RuS (2d): C, 56.27 (56.21); H, 4.34 (4.30); N, 5.36
(5.33). IR data (KBr disc) (cmÀ1): 2036 (υ(Ru―H)), 1947 (υ(CO)),
1582 (υ(C=H;N)), 1379 (υ(N=H;N)), 841 (υ(PFÀ6 )). 1H NMR data in
CDCl3 (δ, ppm): 6.94, 7.14 (imidazolyl-2H), 7.79 (o-H, d, 7.0Hz), 7.50
(m-2H), 7.26 (o′-H) (C6H4S―Me, aromatic H’s), 3.86 (N―CH3, s)
2.41 (S―CH2―CH3, q, J = 7.5 Hz), 1.05 (S―CH2―CH3, t, J = 7.5Hz),
À10.01 (Ru―H, t, J = 20.5 Hz). 13C NMR data (CDCl3, ppm): 153.8
(C-2); 129.0 (C-4); 130.7 (C-5); 155.6 (C-6); 135.8 (C-7); 133.4 (C-8);
130.7 (C-9); 131.2 (C-10); 129.0 (C-11); 192.0 (CO); 36.5 (N―CH3);
31.4 (S―CH2―CH3); 21.7 (S―CH2―CH3); 133.2 (o,o′-C―PPh3),
129.8 (m,m′-C―PPh3) 128.0 (p-C―PPh3). UV–visible (CH3CN):
s
À1 in acetonitrile under N2 atmosphere. The reported potentials are
uncorrected for junction potential and a catalytic oxidation study
was carried out using an Agilent 7890 series GC instrument equip-
ped with a flame ionization detector (FID) with an HP-5 column of
30 m length, 0.53 mm diameter and 5.00 μm film thickness.
Synthesis of Complexes
[RuH(CO)(PPh3)2(SMeaaiNMe)](PF6) (2a)
To a 20 ml acetonitrile suspension of [RuHCl(CO)(PPh3)3] (0.10 g,
0.10 mmol) SMeaaiNMe (1a) (0.024 g, 0.11 mmol) was added
(15 ml acetonitrile) in a 1:1 molar ratio and the solution was
refluxed for 4 h under an N2 atmosphere. The color of the
solution changed from orange-red to dark red. The solvent was
removed under reduced pressure using a rota-evaporator. The
red gummy mass thus left was dissolved in a minimum volume
of methanol and aqueous solution of NH4PF6 was added to
isolate the crystalline products. The precipitate was filtered and
washed with cold water, and finally dried in vacuo over P4O10.
The dry mass was then dissolved in a minimum volume of CH2Cl2
and subjected to chromatographic separation on a silica gel
column (60–120 mesh). The reddish complex [RuH(CO)(PPh3)2
(SMeaaiNMe)](PF6) (2a) was eluted by 1:5 toluene–acetonitrile.
Evaporation of the solvent under reduced pressure afforded pure
complex 2a. The yield was 74 mg (68%). All other compounds
(2b, 2c and 2d) were synthesized following the same procedure
and yield varied from 60% to 70%. Microanalytical data: calcd
(found). For C48H43F6N4OP3RuS (2a): C, 55.87 (55.95); H, 4.17
(4.20); N, 5.43 (5.47). IR data (KBr disc) (cmÀ1): 2034 (υ(Ru―H)),
1939 (υ(CO)), 1584 (υ(C=H;N)), 1371(υ(N=H;N)), 842 (υ(PFÀ6 )).
1H NMR data in CDCl3 (δ, ppm): 6.95, 7.14 (imidazolyl-2H), 7.81
(o-H, d, 7.0Hz), 7.54 (m-2H), 7.28 (o′-H) (C6H4S―Me, aromatic H’s),
3.84 (N―CH3, s), 2.55 (S―CH3, s), À10.07 (Ru―H, t, J = 20.5 Hz).
13C NMR data (CDCl3, ppm): 153.0 (C-2); 129.4 (C-4); 130.6 (C-5);
154.6 (C-6); 135.3 (C-7); 132.9 (C-8); 130.5 (C-9); 130.5 (C-10);
128.9 (C-11); 190.0 (CO); 33.4 (N―CH3); 17.6 (S―CH3);133.9 (o,o′-
C―PPh3), 130.8 (m,m′-C―PPh3) 128.4 (p-C―PPh3). UV–visible
(CH3CN): λmax (ε, MÀ1 cmÀ1): 484 (2204), 357 (2662), 313 (2493).
For C50H47F6N4OP3RuS (2b): C, 56.66 (56.72); H, 4.44 (4.40); N, 5.29
(5.35). IR data (KBr disc) (cmÀ1): 2039 (υ(Ru―H)), 1948 (υ(CO)),
1578 (υ(C=H;N)), 1385 (υ(N=H;N)), 841 (υ(PFÀ6 )). 1H NMR data
in CDCl3 (δ, ppm): 6.94, 7.12 (imidazolyl-2H), 7.78 (o-H, d, 7.0Hz),
7.50 (m-2H), 7,22 (o′-H) (C6H4S―Me, aromatic H’s), 4.19
(N―CH2CH3, q, J = 7.5Hz), 1.44 (N―CH2CH3, t, J =7.5 Hz), 2.44
(S―CH2CH3, q, J = 7.5Hz), 1.04 (S―CH2CH3, t, J = 7.5Hz), À9.98
(Ru―H, t, J = 20.5 Hz). 13C NMR data (CDCl3, ppm): 153.6 (C-2);
128.9 (C-4); 131.0 (C-5); 155.1 (C-6); 136.0 (C-7); 133.2 (C-8); 130.5
λ
max (ε, MÀ1 cmÀ1): 487 (2154), 360 (2952), 311 (3481).
[RuCl(CO)(PPh3)(SκMeaaiNMe)](PF6) (3a) (Sκ abbreviates coordination of ―SR
to Ru(II))
Complex 3a was prepared by refluxing [RuCl2(CO)2(PPh3)2]
(0.090 g, 0.10 mmol) with SMeaaiNMe (1a) (0.028 g, 0.13 mmol)
and the yield was 67 %. Complexes 3b, 3c and 3d were also
prepared by the reaction with 1b, 1c and 1d respectively following
the same procedure as in (2a) with a yield of 63–69%. Microanalyt-
ical data: calcd (found) C30H27ClF6N4OP2RuS (3a): C, 44.80 (44.72); H,
3.36 (3.47); N, 6.97 (7.02). IR data (KBr disc) (cmÀ1): 2002 (υ(CO)),
1581 (υ(C=H;N)), 1356 (υ(N=H;N)), 841 (υ(PF-6)). 1H NMR data in
CDCl3 (δ, ppm): 6.94–7.82 (aromatic H’s), 3.89 (N―CH3, s), 2.85
(S―CH3, s). 13C NMR data (CDCl3, ppm): 156.3 (C-2); 132.4 (C-4);
133.5 (C-5); 156.0 (C-6); 137.0 (C-7); 134.1 (C-8); 131.8 (C-9); 132.6
(C-10); 130.5 (C-11); 195.0 (CO); 36.8 (N―CH3); 21.6 (S―CH3);
135.3 (o,o′-C―PPh3), 131.3 (m,m′-C―PPh3) 129.4 (p-C―PPh3). UV–
visible (CH3CN): λmax (ε, MÀ1 cmÀ1): 494 (1671), 426 (4497), 402
(4061). For C32H31ClF6N4OP2RuS (3b): C, 46.18 (46.13); H, 3.73
(3.66); N, 6.73 (6.78). IR data (KBr disc) (m, cmÀ1): 1997 (υ(CO)),
1577 (υ(C=H;N)), 1359 (υ(N―N)), 841 (υ(PF-6)). 1H NMR data in CDCl3
(δ, ppm): 6.91, 7.12 (imidazolyl-2H), 7.83 (o-H, d, 7.0Hz), 7.54 (m-2H),
7.28 (o′-H) (C6H4S―Me, aromatic H’s), 4.22 (N―CH2―CH3, q,
J = 7.5Hz), 1.43 (N―CH2―CH3, t, J = 7.5Hz), 2.78 (S―CH2―CH3, q,
J = 7.5Hz), 1.22 (S―CH2―CH3, t, J= 7.5 Hz). 13C NMR data (CDCl3,
ppm): 155.4 (C-2); 130.4 (C-4); 132.3 (C-5); 155.8 (C-6); 137.3 (C-7);
135.4 (C-8); 132.8 (C-9); 133.0 (C-10); 129.2 (C-11); 205.5 (CO); 40.0
(N―CH2―CH3); 21.2 (N―CH2―CH3); 30.0 (S―CH2―CH3); 22.4
(S―CH2―CH3); 134.8 (o,o′-C―PPh3), 128.7 (m,m′-C―PPh3) 130.1
(p-C―PPh3). UV–visible (CH3CN): λmax (ε, MÀ1 cmÀ1): 497 (1724),
431 (5012), 396 (4317). For C31H29ClF6N4OP2RuS (3c): C, 45.51
(45.44); H, 3.57 (3.53); N, 6.85 (6.80). IR data (KBr disc) (m, cmÀ1):
1999 (υ(CO)), 1580 (υ(C=H;N)), 1358 (υ(N=H;N)), 841 (υ(PFÀ6 )).
1H NMR data in CDCl3 (δ, ppm): 6.89, 7.11 (imidazolyl-2H), 7.83
(o-H, d, 7.0Hz), 7.52 (m-2H), 7.28 (o′-H) (C6H4S―Me, aromatic H’s),
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Copyright © 2014 John Wiley & Sons, Ltd.
Appl. Organometal. Chem. 2014, 28, 641–651