Pincer Pyridine Diphosphite Complexes of Rhodium and Iridium
ppm. 31P{1H} NMR (CDCl3, 162 MHz): δ = 139.5 (d, JP,Rh
238 Hz) ppm. 13C{1H} NMR (CDCl3, 126 MHz): δ = 164.2 (q,
1JC,B = 49 Hz), 159.1 (br.), 149.0, 147.6, 144.0, 140.0, 136.0 (br.),
=
(15 mL). Subsequently, the filtered solution was concentrated to
around 2 mL and n-hexane (15 mL) was added. The resulting
orange solid was washed with n-hexane (3ϫ10 mL) and vacuum-
130.8, 129.0 (br.), 127.3, 125.5 (br.), 125.4, 121.5, 104.7, 35.7, 34.9, dried; yield 64% (0.033 g). 1H NMR (400 MHz, C6D6, 298 K): δ =
31.5, 31.4, 1.3 ppm. C87H106BN2O6P2Rh (1451.45): calcd. C 71.92,
H 7.36, N 1.93; found C 72.31, H 7.45, N 1.75.
8.26 (br. s, 8 H, H arom., BPh4), 7.67 (br. s, 4 H, H arom.), 7.65
(m, 6 H, H arom., PPh3), 7.37 (br. s, 4 H, H arom.), 7.24 (m, 8 H,
H arom., BPh4), 7.14 (m, 4 H, H arom., BPh4), 6.93 (m, 3 H, H
arom., PPh3), 6.72 (m, 6 H, H arom., PPh3), 6.54 (t, 3JH,H = 8.1 Hz,
[Rh(1)(η2-C2H4)][BPh4] (8): A solution of 4 (0.1 g, 0.089 mmol) in
CH2Cl2 (10 mL) was introduced into a glass pressure reactor and
NaBPh4 (0.03 g, 0.09 mmol) was added. After 1 h, the vessel was
charged with 1 atm of C2H4 and the reaction stirred for 15 h. The
mixture was evaporated down to one-fourth of the volume and n-
3
1 H, Ha arom.), 5.45 (d, JH,H = 8.1 Hz, 2 H, Hb arom.), 1.42 (s,
36 H, 4 CMe3), 1.40 (s, 36 H, 4 CMe3) ppm. 31P{1H} NMR
2
(162 MHz, C6D6, 298 K): δ = 144.1 (d, JP,P = 38.9 Hz, P-O), 11.0
2
(t, JP,P = 38.9 Hz, PPh3) ppm. 13C{1H} NMR (101 MHz, C6D6,
hexane (5 mL) was added to yield 8 as orange crystals (0.045 g,
298 K): δ = 165.3 (q, JC,B = 47.9 Hz), 157.4 (br.), 149.6, 148.8,
146.9, 140.5, 137.0, 135.5 (br.), 134.1 (d, JC,P = 12 Hz), 131.2,
130.7, 129.8 (br.), 128.1, 126.9 (br.), 126.5, 122.9, 104.4 (br.), 36.1,
35.1, 31.6 ppm. C103H118BIrNO6P3 (1761.99): calcd. C 70.21, H
6.75, N 0.79; found C 70.18, H 6.68, N 0.77.
4
35%). 1H NMR (CDCl3, 500 MHz, 298 K): δ = 7.53 (d, JH,H
=
2 Hz, 4 H, 4 H arom.), 7.44 (m, 8 H, 8 H arom., BPh4), 7.29 (d,
4JH,H = 2 Hz, 4 H, 4 H arom.), 7.17 (t, 3JH,H = 8 Hz, 1 H, H arom.,
Ha), 7.00 (t, JH,H = 7 Hz, 8 H, 8 H arom., BPh4), 6.83 (t, JH,H
=
3
7 Hz, 4 H, 4 H arom., BPh4), 6.56 (d, JH,H = 8 Hz, 2 H, 2 H
arom., 2 Hb), 2.98 (br. s, 4 H, C2H4), 1.38 (s, 36 H, 4 CMe3), 1.31
(s, 36 H, 4 CMe3) ppm. 31P{1H} NMR (CDCl3, 162 MHz, 298 K):
[Ir(1)(PPh2Me)][BPh4] (12): Prepared as described for 11 using
1
PPh2Me. Orange solid, yield 67% (0.034 g). H NMR (400 MHz,
δ = 154.2 (d, JP,Rh = 211 Hz) ppm. 13C{1H} NMR (CDCl3,
C6D6, 298 K): δ = 8.22 (br. s, 8 H, H arom., BPh4), 7.70 (br. s, 4
H, H arom.), 7.63 (m, 5 H, H arom., PPh2Me), 7.37 (br. s, 4 H, H
arom.), 7.25 (m, 8 H, H arom., BPh4), 7.12 (m, 4 H, H arom.,
BPh4), 6.92 (m, 5 H, H arom., PPh2Me), 6.55 (t, 3JH,H = 7.8 Hz, 1
1
126 MHz, 298 K): δ = 164.3 (q, JC,B = 49 Hz), 156.9 (t, JP,C
=
6 Hz), 149.8, 147.1, 144.2 (br.), 139.7, 136.3 (br.), 130.4, 127.6,
125.8, 125.6 (br.), 121.6, 105.6 (br.), 57.7 (br.), 35.7, 35.0, 31.4,
31.3 ppm. C87H107BNO6P2Rh (1438.45): calcd. C 72.64, H 7.50, N
0.97; found C 72.81, H 7.98, N 0.90.
3
H, Ha arom.), 5.62 (d, JH,H = 7.8 Hz, 2 H, Hb arom.), 1.48 (s, 36
H, 4 CMe3), 1.43 (br. s, 3 H, PPh2Me), 1.37 (s, 36 H, 4 CMe3)
2
ppm. 31P{1H} NMR (162 MHz, C6D6, 298 K): δ = 146.5 (d, JP,P
[Rh(1)(CO)][BPh4] (9): Obtained as yellow crystals as described for
2
= 35.1 Hz, P–O), 6.2 (t, JP,P = 35.1 Hz, PPh2Me) ppm. 13C{1H}
8 using CO instead of C2H4 (0.05 g, 40%). IR (nujol mull): ν =
˜
NMR (101 MHz, C6D6, 298 K): δ = 169.3 (q, JC,B = 42 Hz), 153.2
(br.), 149.8, 148.6, 144.9, 140.6, 137.3, 132.7 (br.), 131.7, 131.5 (br.),
130.9 (br.), 129.7, 129.5 (br.), 126.7, 125.8, 101.4 (br.), 35.9, 35.1,
31.6, 31.1 ppm. C98H116BIrNO6P3 (1699.92): calcd. C 69.24, H
6.88, N 0.82; found C 69.21, H 6.88, N 0.75.
2093 (s, CO) cm–1. 1H NMR (CD2Cl2, 500 MHz): δ = 7.80 (t, 3JH,H
= 8 Hz, 1 H, H arom.), 7.61 (br. s, 4 H, 4 H arom.), 7.34 (br. s, 12
H, 12 H arom.), 7.02 (t, JH,H = 7 Hz, 8 H, 8 H arom., BPh4), 6.86
(m, 6 H, 6 H arom.), 1.46 (s, 36 H, 4 CMe3), 1.40 (s, 36 H, 4 CMe3)
ppm. 31P{1H} NMR (CDCl3, 202 MHz, 298 K): δ = 145.6 (d, JP,Rh
= 220 Hz) ppm. 13C{1H} NMR (CD2Cl2, 126 MHz, 298 K): δ =
[Ir(1)(CNBn)2][BPh4] (13): Isocyanide (0.04 mmol) and NaBPh4
(0.013 g, 0.04 mmol) were added to a solution of complex 5
(0.036 g, 0.03 mmol) in THF (10 mL). The resulting solution was
stirred at room temperature for 1 h and the volatile compounds
were removed under vacuum. The residue was extracted with tolu-
ene (15 mL). Subsequently, the filtered solution was concentrated
to around 2 mL and n-hexane (15 mL) was added. The resulting
yellow solid was washed with n-hexane (3ϫ10 mL) and vacuum-
1
2
1
185.7 (m, JC,Rh = 72, JC,P = 16 Hz), 164.4 (q, JC,B = 49 Hz),
157.8 (br.), 150.4, 147.1, 144.1 (br.), 140.2, 136.2 (br.), 130.7, 127.9,
126.6, 126.3, 125.9, 122.0, 106.4, 36.0, 35.2, 31.6, 31.3 ppm.
C86H103BNO7P2Rh (1438.40): calcd. C 71.81, H 7.22, N 0.97;
found C 71.81, H 7.54, N 0.76.
[Rh(1)(CNXy)][BPh4] (10): NaBPh4 (0.013 g, 0.04 mmol) was
added to a solution of 4 (0.043 g, 0.04 mmol) in THF (2 mL). The
mixture was stirred for 1 h, and CNXy (0.005 g, 0.04 mmol) was
added. The reaction was stirred overnight. Solvent was removed
under reduced pressure. The resulting residue was dissolved in
CH2Cl2 and filtered through a short pad of Celite. The solution
was dried and the solid was washed with Et2O (2ϫ5 mL) to yield
dried; yield 71% (0.037 g). IR (KBr): ν = 2191 (br. s, CN) cm–1.
˜
31P{1H} NMR (162 MHz, C6D6, 298 K): δ = 145.2 (s) ppm. 1H
NMR (400 MHz, C6D6, 298 K): δ = 8.22 (br. s, 8 H, H arom.,
BPh4), 7.74 (d, JH,H = 2.4 Hz, 4 H, H arom.), 7.49 (d, JH,H
=
2.4 Hz, 4 H, H arom.), 7.36 (t, JH,H = 7.0 Hz, 8 H, H arom., BPh4),
7.24 (m, 4 H, H arom., BPh4), 7.15 (br. s, 4 H, 10 H, CNCH2C6H5),
10 as an orange solid (0.042 g, 80%). IR (CH Cl ): ν = 2153 (s,
˜
2
2
3
3
6.83 (t, JH,H = 7.8 Hz, 1 H, Ha arom.), 6.18 (d, JH,H = 7.8 Hz, 2
H, Hb arom.), 2.22 (s, 4 H, 2CNCH2C6H5), 1.42 (s, 36 H, 4 CMe3),
1.40 (s, 36 H, 4 CMe3) ppm. 13C{1H} NMR (101 MHz, C6D6,
298 K): δ = 164.8 (q, JC,B = 52.0 Hz), 157.9 (br.), 149.5, 148.7,
146.0, 144.8 (br.), 140.8, 137.0 (br.), 136.9, 133.9, 132.8, 131.0,
128.3, 127.2 (br.), 126.2, 122.1, 104.7 (br.), 48.0, 35.5, 34.3,
31.2 ppm. C101H117BIrN3O6P2 (1734.00): calcd. C 69.95, H 6.80, N
2.42; found C 69.93, H 6.88, N 2.45.
CN) cm–1. 1H NMR (CD2Cl2, 300 MHz, 298 K): δ = 7.86 (t, 3JH,H
4
= 9.0 Hz, 1 H, 1 H arom.), 7.59 (d, JH,H = 2.1 Hz, 4 H, 4 H
arom.), 7.36 (m, 13 H, 13 H arom.), 7.08 (m, 8 H, 8 H arom.), 6.89
(m, 8 H, 8 H arom.), 1.58 (s, 6 H, 2 Me), 1.49 (s, 36 H, 4 CMe3),
1.42 (s, 36 H, 4 CMe3) ppm. 1P{1H} NMR (CD2Cl2, 121 MHz,
298 K): δ = 149.8 (d, JP,Rh = 235 Hz) ppm. 13C{1H} NMR
(CD2Cl2, 75 MHz, 298 K): δ = 164.4 (q, JC,B = 52 Hz), 164.4 (m),
158.4 (m), 149.9, 147.1, 144.2, 140.6, 136.3, 135.6, 131.1, 129.9,
128.2, 127.8, 127.0, 126.1, 125.9, 122.0, 105.7, 36.0, 35.2, 31.8, 31.5,
18.1 ppm. C94H112BN2O6P2Rh (1541.57): calcd. C 73.24, H 7.32,
N 1.82; found C 72.67, H 7.33, N 1.73.
[Ir(1)(CNCy)2][BPh4] (14): Prepared as described for 13. Yellow so-
lid, yield 77% (0.034 g). IR (KBr): ν = 2178 (s, CN) cm–1. 31P{1H}
˜
NMR (121 MHz, C6D6, 298 K): δ = 146.3 (s) ppm. 1H NMR
(400 MHz, C6D6, 298 K): δ = 8.13 (br. s, 8 H, H arom., BPh4), 7.78
(m, 4 H, H arom.), 7.50 (br. s, 4 H, H arom), 7.43 (br. s, 8 H, H
arom., BPh4), 7.14 (br. s, 4 H, 4 H arom., BPh4), 6.57 (m, 1 H, Ha
[Ir(1)(PPh3)][BPh4] (11): PPh3 (0.010 g, 0.04 mmol) and NaBPh4
(0.013 g, 0.04 mmol) was added to a solution of complex 5 (0.036 g,
0.03 mmol) in THF (10 mL). The resulting solution was stirred at
room temperature for 1 h and the volatile compounds were re-
moved under vacuum. The residue was extracted with toluene
3
arom.), 5.73 (d, JH,H = 9.8 Hz, 2 H, Hb arom.), 2.22 (br. s, 2 H,
2CHCNC6H11), 1.83 (m, 12 H, CNC6H11), 1.62 (s, 36 H, 4 CMe3),
Eur. J. Inorg. Chem. 2012, 655–663
© 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
661