Organometallics
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4.88 (s, 5H, C5H5), 4.44 (d, 2H, JHH = 6.0 Hz, CH2);40 13C{1H}
(75 MHz) 205.9 (s, CO), 153.5 (s, C11), 146.5 (s, C2), 143.5 (s, C9),
132.5 (s, C8), 138.0 (s, i-C6H5), 128.5 and 128.2 (2 × s, o- and m-C6H5),
128.8 (s, p-C6H5), 124.4 and 123.9 (2 × s, C5 and C6), 118.5 (s, C4),
112.1 (s, C7), 83.0 (s, C5H5), 45.6 (s, CH2); 31P{1H} (121 MHz)
−143.3 (sep, 1JPF = 706.5 Hz). IR (cm−1, powder film): 3391 (m), 1940
(s, νCO), 1671 (s), 1570 (s), 1536 (s), 1463 (s), 1230 (m), 831 (vs),
736 (s), 556 (vs). UV−visible (nm, 1.99 × 10−5 M in MeOH (ε,
film): 3395 (m), 2948 (m), 2866 (w), 1927 (s, νCO), 1673 (m), 1588
(m), 1535 (s), 1464 (s), 1256 (m), 823 (vs), 738 (s), 555 (vs).
UV−visible (nm, 2.20 × 10−5 M in MeOH (ε, M−1 cm−1)): 296 (4480),
318 (4180).
3
Separation of Diastereomers of 6c+PF6−. A round-bottom flask
−
was charged with 5+PF6 (0.545 g, 1.29 mmol), (RCRC)-4c (0.510 g,
1.70 mmol), CH2Cl2 (12 mL), and MeOH (6 mL) with stirring. After
3 days, the solvent was removed by oil pump vacuum and the residue
was chromatographed on an alumina column (3 × 20 cm with CH2Cl2/
MeOH, 100/2.5 v/v (1000 mL) → 100/3.0 v/v (500 mL) → 100/3.5
v/v (500 mL) → 100/4.0 v/v (500 mL) → 100/6.0 v/v (500 mL) →
100/10.0 v/v (500 mL)). Three fractions, the first and the third con-
taining one diastereomer and the second a mixture, were collected. The
solvents were removed from the first and third fractions by rotary
evaporation to give (RRuRCRC)-6c+X− (0.290 g) and (SRuRCRC)-6c+X−
(0.220 g) as pale yellow-brown and pale brown solids, respectively,
M
−1 cm−1)): 292 (8150).
−
(RRuSC/SRuSC)-[(η5-C5H5)Ru(CO)(4b)]+PF6 ((RRuSC/SRuSC)-
−
6b+PF6−). A round-bottom flask was charged with 5+PF6 (0.100 g,
0.237 mmol), (SC)-4b (0.066 g, 0.24 mmol), CH2Cl2 (2 mL), and
MeOH (1 mL) with stirring. After 2 days, the solvent was removed by oil
pump vacuum and the residue was chromatographed on a silica gel
column (1 × 15 cm, 3/1 v/v CH2Cl2/CH3CN). The solvent was
removed from the product-containing fractions. The sticky yellow solid
was dissolved in CH2Cl2 (5 mL), and pentane was added until a
precipitate formed. The solvent was removed by oil pump vacuum.
More pentane (5 mL) was added and removed by oil pump vacuum
(2×) to give (RRuSC/SRuSC)-6b+PF6− as a yellow powder (0.103 g, 0.168
mmol, 71%) and a 54/46 mixture of Ru,C configurational dia-
stereomers. Anal. Calcd for C22H22F6N5OPRu: C, 42.72; H, 3.59; N,
11.32. Found: C, 43.00; H, 4.19; N, 10.38.39
−
where X− is principally derived from the alumina (<10% PF6 ).
(RRuRCRC)-6c+X–. NMR (δ, CD3CN):37 1H (500 MHz) 7.24−7.22
(m, 1H, CH4/7), 7.07−6.98 (m, 3H, CH5, CH6, and CH4/7), 6.42
(br s, 2H, NH), 6.14 (br s, 1H, NH), 5.22 (br s, 1H, NH), 5.04 (s, 5H,
C5H5), 3.33−3.31 (m, 1H, CHNH), 2.31−2.27 (m, 1H, CHN(CH3)2),
2.23−2.19 (m, 1H), 2.08 (s, 6H, N(CH3)2), 1.80−1.74, 1.67−1.65,
1.32−1.13 (3 × m, 1H, 1H 4H, remaining aliphatic CH); 13C{1H} (125
MHz) 207.6 (s, CO), 157.0 (s, C11), 153.2 (s, C2), 146.0 (s, C9), 138.4
(s, C8), 121.3, 121.0 (2 × s, C5 and C6), 116.5 (s, C4), 112.9 (s, C7),
83.4 (s, C5H5), 67.9 (s, CHN(CH3)2), 52.9 (s, CHNH), 40.3 (s,
N(CH3)2), 33.5 (s, CH2), 25.6, 25.1, 22.7 (3 × s, remaining 3 CH2).
NMR (δ, CD3CN; signals for diastereomers are separated by
slashes):37 1H (300 MHz) 7.47−7.18 (m, 9H, CH4−7 and C6H5), 6.26
(br m, 1H, NH), 5.11 (br s, 1H, NH), 5.05/4.60 (2 × s, 54:46, 5H, C5H5),
3
4.77−4.66 (m, 1H, CH), 1.51/1.49 (2 × d, 3H, JHH = 4.8/4.8 Hz,
CH3);40 13C{1H} (75 MHz) 205.9/205.4 (2 × s, CO), 152.9/152.7 (2 ×
s, C11), 146.2/146.0 (2 × s, C2), 143.8, 143.35, 143.31, 143.26 (4 × s,
C9 and i-C6H5 diastereomers), 132.4/132.3 (2 × s, C8), 129.90/129.87
(2 × s, m-C6H5),41 126.9/126.8 (2 × s, o-C6H5), 128.9/128.8 (2 × s,
p-C6H5), 124.47/124.45, 124.03/124.00 (4 × s, C5 and C6), 118.60/
118.53 (2 × s, C4), 112.1 (s, C7), 83.1/82.8 (2 × s, C5H5), 52.7/52.5
(2 × s, CH), 23.7/23.6 (2 × s, CH3); 31P{1H} (121 MHz) −143.2 (sep,
1JPF = 706.6 Hz). IR (cm−1, powder film): 3402 (m), 1943 (s, νCO), 1670
(s), 1570 (s), 1537 (s), 1463 (s), 1229 (m), 833 (vs), 738 (s), 556 (vs).
UV−visible (nm, 1.88 × 10−5 M in MeOH (ε, M−1 cm−1)): 295 (8050),
322 (4480). [α]24589 = −15.4° 0.4° (1.94 mg mL−1, MeOH).
37
(SRuRCRC)-6c+X–. NMR (δ, CD3CN): H (500 MHz) 7.19−7.18
(m, 1H, CH4/7), 7.05−6.98 (m, 2H, CH5 and CH6), 5.92 (br s, 1H,
NH), 5.27 (br s, 2H, NH), 5.07 (s, 5H, C5H5), 4.89 (br s, 1H, NH),
3.41−3.28 (m, 1H, CHNH), 2.39−2.33 (m, 1H, CHN(CH3)2), 2.26
(s, 6H, N(CH3)2), 2.09−2.05, 1.86−1.84, 1.77−1.74, 1.65−1.62, 1.34−
1.10 (5 × m, 1H, 1H, 1H, 1H, 4H, remaining aliphatic CH);40 13C{1H}
(125 MHz) 207.6 (s, CO), 157.7 (s, C11), 153.4 (s, C2), 145.8 (s, C9),
136.8 (s, C8), 121.4, 121.3 (2 × s, C5 and C6), 116.4 (s, C4), 112.0 (s,
C7), 83.7 (s, C5H5), 68.1 (s, CHN(CH3)2), 53.0 (s, CHNH), 40.5 (s,
N(CH3)2), 34.4 (s, CH2), 25.5, 25.2, 22.9 (3 × s, remaining 3 CH2).
A round-bottom flask was charged with (RRuRCRC)-6c+X− (0.049 g,
ca. 0.1 mmol if the mass is considered to represent the cation) and
1
−
(RRuRCRC/SRuRCRC)-[(η5-C5H5)Ru(CO)(4c)]+PF6 ((RRuRCRC−/
SRuRCRC)-6c+PF6−). A round-bottom flask was charged with 5+PF6
(0.090 g, 0.21 mmol), (RCRC)-4c (0.064 g, 0.21 mmol), CH2Cl2 (2 mL),
and MeOH (1 mL) with stirring. After 2 days, the solvent was removed
by oil pump vacuum and the residue was chromatographed on an
alumina column (1 × 10 cm, 100/1 → 95/5 v/v CH2Cl2/MeOH). An
impurity eluted first, followed by impurity/product fractions and then
product-containing fractions. The solvent was removed from the last set
to give a yellow-brown solid. The solid was dissolved in CH2Cl2 (5 mL)
and added to a suspension of Na+PF6− (0.143 g, 0.851 mmol) in CH2Cl2
(5 mL). The mixture was stirred overnight and filtered through a plug
of Celite (1 × 5 cm), which was washed with CH2Cl2 (150 mL). The
solvent was removed from the filtrate by rotary evaporation. The sticky
yellow solid was dissolved in CH2Cl2 (5 mL), and pentane was added
until a precipitate formed. The solvent was removed by oil pump
vacuum. More pentane (5 mL) was added and removed by oil pump
+
−
CH2Cl2 (5 mL) and was placed in a −40 °C cold bath. Then NH4 PF6
(0.143 g, 0.851 mmol) was added with stirring. After 17 h, the mixture
was filtered through a plug of Celite (0.1 × 3 cm), which was washed
with additional CH2Cl2 (2 mL). The solvent was removed from the
filtrate by rotary evaporation. The sticky yellow-brown solid was dis-
solved in CH2Cl2 (1 mL), and pentane was added until a precipitate
formed. The solvent was removed by oil pump vacuum. More pentane
(5 mL) was added and removed by oil pump vacuum (2 × ) to give
(RRuRCRC)-6c+PF6− as a yellow-brown powder (0.032 g, 0.050 mmol;
99/01 RRuRCRC/SRuRCRC, configurations assigned crystallographically).
Anal. Calcd for C22H29F6N6OPRu: C, 41.32; H, 4.57; F, 17.82; N, 13.14.
Found: C, 40.92; H, 4.92; F, 16.24; N, 12.19.39
NMR (δ, CD3CN):37 1H (500 MHz) 7.22 (d, 1H, JHH = 7.7 Hz,
3
CH4/7), 7.12−7.05 (m, 3H, CH5, CH6, and CH4/7), 5.04 (s, 5H,
C5H5), 4.97 (br s, 1H, NH) 4.65 (br s, 1H, NH), 3.59−3.55 (m, 1H,
CHNH), 2.82−2.74 (m, 1H, CHN(CH3)2), 2.74 (s, 6H, N(CH3)2),
2.05−2.03, 1.86−1.83, 1.75−1.77, 1.48−1.40, 1.36−1.24 (5 × m, 2H,
1H, 1H, 1H, 3H, remaining aliphatic CH);40 13C{1H} (125 MHz) 208.1
(s, CO), 160.2 (s, C11), 153.7 (s, C2), 144.9 (s, C9), 133.1 (2 × s, C8),
122.5, 122.4 (2 × s, C5 and C6), 117.3 (s, C4), 110.4 (s, C7), 83.6 (s,
C5H5), 72.8 (s, CHN(CH3)2), 53.4 (s, CHNH), 41.3 (s, N(CH3)2),
33.1, 24.9, 24.6, 24.6 (4 × s, remaining 4 CH2); 19F{1H} (470 MHz)
−72.89 (d, 1JFP = 706.41 Hz). IR (cm−1, powder film): 3412 (m), 2937
(m), 2866 (w), 1923 (s, νCO), 1680 (m), 1589 (m), 1535 (s), 1463 (s),
1255 (m), 1222 (m), 833 (vs), 740 (s). UV−visible (nm, 2.20 × 10−5 M
in MeOH (ε, M−1 cm−1)): 294 (11923), 314 (10384). CD (nm, 2.6 ×
10−3 M in CH3CN ([θ], deg L mol−1 cm−1, and Δε, L mol−1 cm−1)):
408 (−268 and −0.089), 368 (+58.0 and +0.019).
−
vacuum (2×) to give (RRuRCRC/SRuRCRC)-6c+PF6 as a green-brown
powder (0.078 g, 0.119 mmol, 57%) as a mixture of Ru,C configurational
diastereomers.44
NMR (δ, CD3CN; signals for diastereomers are separated by
slashes):37 1H (300 MHz) 7.36−7.25 (m, 1H, CH4/7), 7.19−7.05 (m,
3H, CH7/4, CH5, and CH6), 5.17−5.12 (br m, 1H, NH), 5.08/5.05
(2 × s, 5H, C5H5), 3.71−3.53 (two overlapping br m, 1H, CHNH),
3.07−2.84 (m, 1H, CHN(CH3)2), 2.77/2.75 (2 × s, 6H, N(CH3)2),
2.09−2.00, 1.92−1.81, 1.80−1.70, 1.55−1.23 (4 × m, 2H, 1H, 1H, 4H,
remaining aliphatic CH);40 13C{1H} (125 MHz) 207.7/207.1 (2 × s,
CO), 157.0 (br s, C11), 151.0 (br s, C2), 144.6/144.5 (2 × s, C9),
132.92/132.85 (2 × s, C8), 123.1/123.045/122.9 (3 × s, C5 and C6),
117.63/117.59 (2 × s, C4), 111.0/110.8 (2 × s, C7), 83.6/83.5 (2 × s,
C5H5), 72.0/70.9 (2 × s, CHN(CH3)2), 53.0/52.0 (2 × s, CHNH),
41.2/41.0 (2 × br s, N(CH3)2), 33.3/33.2 (2 × s, CH2), 24.90, 24.87,
24.52, 24.46, 24.42, 24.00 (6 × s, remaining 3 CH2). IR (cm−1, powder
A round-bottom flask was charged with (SRuRCRC)-6c+X− (0.049 g,
0.1 mmol if the mass is considered to represent the cation) and CH2Cl2
+
(5 mL) and was placed in a −40 °C cold bath. Then NH4 PF6− (0.143 g,
L
dx.doi.org/10.1021/om500705s | Organometallics XXXX, XXX, XXX−XXX