JOURNAL OF COORDINATION CHEMISTRY
5
1
observed 399.20 (M); Calcd 399.44 (M). H NMR (CDCl , δ): 8.74 (2H, d, H ), 8.66 (4H, s, H ),
7
3
A
G,J
1
3
.86 (2H, t, H ), 7.36 (2H, m, H ), 7.07 (2H, dd, H ), 3.99 (6H, s, H ), 3.93 (3H, s, H ). C NMR
D C B M N
(
CDCl , δ): 156.24 C , 155.90 C , 153.64 C , 150.56 C , 149.17 C , 139.00 C , 136.94 C , 134.55
3 F E A H K C L
C , 123.89 C , 121.47 C , 118.99 C , 104.69 C , 61.02 C , 56.56 C .
I
B
D
G
J
N
M
2
.2.1.3. 2-(2-Pyridyl)-4-carboxyquinoline (pcqH). The ligand was prepared according to
literature method [37]. 18 g (0.12 mol) of 23-indolinedione was crushed to powder and mixed
with 15 g (0.12 mol) of 2-acetylpyridine for ~30 min. 60 g (~60 mL) of 33% NaOH were added
at 5 °C with stirring. The solution was stirred continuously for 30 min when the temperature
rises to ~50 °C. Ice flakes were added to the mixture. Stirring the mixture with a glass rod
produced a purple red solid. The solid was filtered, washed with water followed by cold
acetone. The crude product was recrystallized from water to give a light purple crystal (yield:
+
1
8 g, 67%). Mass spectrum (ESI + ve) (m/z): base peak: 295 (M + 23 + 23) 23 = mass of Na .
2
.2.1.4. [Ru(L1)Cl3]. L1 (1.5 mmol) and RuCl (0.40 g, 1.5 mmol) were dissolved in 20 mL of
3
dry methanol and heated to reflux under N for 3 h. The resulting deep brown solution was
2
allowed to cool at room temperature, after which the solution was cooled in an ice-bath for
0.5 h. The brown solid was collected by vacuum filtration and washed with cold methanol
until the filtrate was colorless and then washed with Et O and air-dried. The product (yield:
2
0.662 g, 72%) was used without further purification.
2
.2.1.5. [Ru(L1)(pcqH)NCS](PF ) (1). [Ru(L1)Cl ] (0.5 mmol) and pcqH (0.125 g, 0.5 mmol)
6
3
were taken in a round-bottomed flask in 25 mL DMF and refluxed for 6 h under N .The reaction
2
mixture was then reduced in a rotatory evaporator to 5 mL and a saturated aqueous solution
of NH PF was added to the solution. On addition of more water, precipitate appeared which
4
6
was collected by filtration in a G4 sintered glass filter. The product was purified by column
chromatography using silica as the stationary phase and DCM as mobile phase, eluted with
1
: 1 DCM/CH OH eluent. This chloro-complex (101 mg, 0.104 mmol) was further reacted with
3
ammonium thiocyanate (279 mg (excess)) in 20 mL DMF and refluxed for 5 h to give a reddish
solution which was reduced in a rotatory evaporator to 5 mL and then saturated aq. solution
of NH PF was added to the solution to give reddish precipitate. The precipitate was washed
4
6
with water, dried, washed with ether and collected by filtration in a G4 sintered glass filter.
Crude weight: 95 mg. The product was purified by column chromatography using silica as
the stationary phase and DCM as mobile phase. The deep red product (26 mg, 0.031 mmol,
−1
yield 29.5%) is eluted with 1 : 1 DCM/CH OH eluent (scheme 1). FTIR (cm ): 3383 (broad),
3
2
102, 1600, 1400, 1200, 786. Mass spectrum (ESI + ve): observed 749 (M + 1); Calcd: 748 (M).
1
H NMR (d -DMSO, δ): 9.6–9.4 (1H, d, H ), 9.212 (2H, s, H ), 8.99–8.91 (3H, d, HA,m), 8.79 (1H, s,
6
a
G
H ), 8.4–8.3 (3H, t, H ), 8.1–8.0 (3H, m, H ), 7.83–7.80 (2H, d, H ), 7.66–7.61 (2H, m, H ), 7.40
g
B,d
l,k,j
D
C
(
2H, m, H ), 7.26 (2H, m, H ), 7.2–7.1 (2H, m, H ), 3.82 (3H, s, OMe-C ).
J c, K L
2
.2.1.6. [Ru(L2)(pcqH)NCS](PF ) (2). Complex 2 was prepared in the same method as 1
6
−1
(
Yield: 28.5%). FTIR (cm ): 3000 (broad), 2098, 1600, 1400, 1265, 844, 786. Mass spectrum
1
(
ESI + ve): observed 809.72 (M + 1); Calcd 808 (M). H NMR (d -DMSO, δ): 9.4 (1H, d, H ), 9.13
6
a
(
2H, s, H ), 8.96 (2H, d, H ), 8.92 (1H, d, H ), 8.81 (1H, d, H ), 8.79 (1H, s, H ), 8.1 (2H, t, H ),
G A m d g B
7
.84 (3H, m, H ), 7.64 (2H, d, H ), 7.57 (2H, m, H ), 7.4 (2H, m, H ), 7.2 (1H, m, H ), 4.02 (6H, s,
l,k,j D C J c
OMe-C ), 3.945 (3H, s, OMe-C ).
K
L