C-H Activated Rh(III) and Ir(III) Complexes
Organometallics, Vol. 18, No. 11, 1999 2203
-CH2-), 0.96 (t) and 0.95 (t) (3J HH ) 6.6 Hz, 3H, -CH3). Anal.
Calcd for C22H21O2P: C, 75.8; H, 6.1; P, 8.9. Found: C, 75.5;
H, 6.3; P, 8.9.
Ta ble 4. Com p a r ison of Str u ctu r a l Da ta (Bon d
Len gth s in Å, An gles in d eg) for Com p lexes 1 a n d 4
complex 1
complex 4
Rea ction of [µ-Rh Cl(2,5-NBD)]2 w ith DP ES. F or m a tion
of [Rh Cl(2,5-NBD)(DP ES)] (1). A dichloromethane solution
(10 mL) of [µ-RhCl(2,5-NBD)]2 (50.2 mg, 0.109 mmol) and
DPES (76.6 mg, 0.220 mmol) was stirred for 1 h at room
temperature. The solution was reduced to ca. 2 mL, and diethyl
ether (35 mL) was added, forming a bright yellow air-stable
precipitate. The powder was collected by filtration, washed
with diethyl ether (2 × 10 mL), and dried under vacuum.
Yield: 130 mg (73%). Yellow crystals were obtained by slow
diffusion of diethyl ether into a dichloromethane solution of
Ma-P
2.3016(8)
1.845(3)
1.402(4)
1.501(4)
1.432(3)
1.342(4)
1.177(5)
1.518(5)
1.476(6)
2.290(1)
1.821(5)
1.394(6)
1.502(7)
1.524(5)
1.277(7)
1.262(6)
1.480(7)
1.473(15)
P-C10
C10-C5
C5-C4
C4-O1
O1-C3
C3-O2
C3-C2
C2-C1
Ma-P-C10
P-C10-C5
C10-C5-C4
C5-C4-O1
C4-O1-C3
O1-C3-O2
O1-C3-C2
C3-C2-C1
112.79(9)
121.1(2)
121.5(2)
109.1(2)
117.0(3)
122.8(3)
109.7(3)
113.3(4)
101.7(2)
112.7(3)
118.5(4)
105.9(4)
117.7(4)
123.8(5)
116.5(7)
116.3(7)
1
3
1. H NMR: δ 7.66-7.19 (m, 13H, Ar), 6.85 (dd, J HH ) 10.5,
7.8 Hz, 1H, Ar), 6.12 (s, 2H, Ar-CH2-), 5.25 (bs, 2H, NBD),
3
3.83 (bs, 2H, NBD), 3.15 (bs, 2H, NBD), 2.32 (q, J HH ) 7.5
3
Hz, 2H, -CH2-), 1.42 (bs, 2H, NBD), 1.16 (t, J HH ) 7.5 Hz,
3H, -CH3). Anal. Calcd for C29H29ClO2PRh: C, 60.2; H, 5.1;
P, 5.4. Found: C, 60.3; H, 5.2; P, 5.4.
Rea ction of [µ-Ir Cl(1,5-COD)]2 w ith DP ES. F or m a tion
of [Ir Cl(1,5-COD)(DP ES)] (2). Using a procedure similar to
that for 1 with [µ-IrCl(1,5-COD)]2 (30.2 mg, 44.9 µmol) and
DPES (31.6 mg, 90.8 µmol) gave complex 2 as an air-stable
bright yellow powder. Yield: 50.3 mg (81%). 1H NMR: δ 7.71-
7.08 (m, 14H, Ar), 5.78 (s, 2H, Ar-CH2-), 5.16 (bs, 2H, COD),
3.00 (bs, 2H, COD), 2.34 (q, 3J HH ) 7.5 Hz, 2H, -CH2-), 2.26-
a
M ) Rh (1), Ir (4).
bond distances are all due to coordination of the carbo-
nyl functionality in 4.
Exp er im en ta l Section
3
1.28 (m, 8H, COD), 1.16 (t, J HH ) 7.5 Hz, 3H, -CH3). Anal.
Calcd for C30H33ClO2PIr: C, 53.0; H, 4.8, P, 4.3. Found: C,
53.2; H, 5.2; P, 4.3.
The apparatuses, general procedures, and purification of
solvents have been previously described.15 Pyridine was dried
with powdered potassium hydroxide, followed by distillation
over calcium dihydride, and used immediately. Propionyl
chloride was distilled and used immediately. Commercially
available reagents were purchased and used without further
purification. The compound DPBE19 and the complexes [µ-RhCl-
(2,5-NBD)]2,26 [µ-IrCl(1,5-COD)]2,27 [Ir(1,5-COD)2][BF4],28 [Rh-
(2,5-NBD)2][CF3SO3],28 [µ-IrCl(C8H14)2]2,29 and [Rh(2,5-NBD)-
(PPh3)2][PF6]30 were prepared according to literature procedures.
The tertiary phosphines are hygroscopic, but once isolated as
pure solids they are relatively stable toward oxygen.
Rea ction of [Rh (2,5-NBD)2][CF 3SO3] w ith DP ES. F or -
m a tion of [Rh (2,5-NBD)(DP ES)][CF 3SO3] (3). [Rh(2,5-
NBD)2][CF3SO3] (53.2 mg, 0.122 mmol) and DPES (42.7 mg,
0.123 mmol) were dissolved in dichloromethane (10 mL). After
the bright yellow solution was stirred for 30 min, the solvent
was concentrated under vacuum to ca. 2 mL. Dropwise addi-
tion of n-hexane (20 mL) gave a yellow precipitate. Removal
of the solvent and drying under vacuum gave the air-sensitive
complex 3. Yield: 43.1 mg (51%). 1H NMR (-40 °C in CD2-
Cl2): δ 7.75-6.89 (m, 14H, Ar), 6.27 (bs, 2H, Ar-CH2-), 5.41
(bs, 2H, NBD), 3.92 (bs, 2H, NBD), 3.46 (bs, 2H, NBD), 2.14
1H and 31P NMR spectra were recorded at 300 and 121 MHz,
3
(q, J HH ) 7.7 Hz, 2H, -CH2-) 1.43 (bs, 2H, NBD), 0.91 (t,
respectively, using a Varian Unity 300 MHz spectrometer. 13
C
3J HH ) 7.7 Hz, 3H, -CH3). Anal. Calcd for C30H29F3O5PSRh:
C, 52.1; H, 4.2; P, 4.5. Found: C, 52.9; H, 5.0; P, 4.3.
and HMQC (2D inverse H,C correlation) NMR spectra were
recorded at 125 and 500 MHz, respectively, using a Bruker
ARX 500 MHz spectrometer. Unless otherwise stated, the
NMR measurements were performed in CDCl3.
Rea ction of [Ir (1,5-COD)2][BF 4] w ith DP ES. F or m a tion
of [Ir H(1,5-COD)(DP ES)][BF 4] (4). When [Ir(1,5-COD)2]-
[BF4] (91.3 mg, 0.184 mmol) and DPES (64.3 mg, 0.184 mmol)
were mixed in dichloromethane (10 mL), the solution gradually
changed color from dark red to light yellow within minutes.
After 45 min an off-white powder was isolated by evaporation
of the solvent and washed with diethyl ether (3 × 10 mL) and
n-hexane (3 × 10 mL). Yield: 115 mg (83%). This air-stable
product can be recrystallized by slow diffusion of diethyl ether
into a solution of acetone. 1H NMR: δ 7.79-7.03 (m, 14H, Ar),
6.87 (d, 3J PH ) 1.8 Hz, 1H, Ar-C(R)H-Ir), 5.86 (m, 1H, COD),
5.25 (m, 1H, COD), 4.68 (m, 2H, COD), 2.76-2.34 (m, 8H,
COD), 2.24-1.86 (m, 2H, -CH2-), 0.68 (t, 3J HH ) 7.8 Hz, 3H,
Syn th esis of o-(Dip h en ylp h osp h in o)ben zoic Acid Eth -
yl Ester , (o-P h 2P C6H4CH2OC(O)Et) (DP ES). A solution of
o-(diphenylphosphino)benzyl alcohol10d (2.74 g, 9.39 mmol) and
pyridine (2.25 g, 28.4 mmol) in THF (10 mL) was vigorously
stirred. Propionyl chloride (0.902 g, 9.75 mmol) was added
through a septum with a syringe, and the suspension was
stirred for 1.5 h. The precipitate was removed by Schlenk
filtration and washed with THF (3 × 20 mL). Evaporation of
the combined filtrates yielded a yellow, viscous oil. The oil was
dissolved in diethyl ether (40 mL), the solution was washed
with water (5 × 30 mL), and the organic phase was dried with
magnesium sulfate. The solution was filtered and reduced to
ca. 2 mL, and n-pentane (100 mL) was added to the remaining
oil. The cloudy solution was stored overnight at -18 °C, and
the resulting white needles were isolated by filtration and
dried under vacuum. Yield: 2.0 g (61%). 1H NMR: δ 7.48-
2
-CH3), -19.2 (d, J PH ) 13 Hz, 1H, Ir-H). 13C{1H} NMR: δ
2
187.8 (s, -C(O)-), 154-126 (m, Ar), 99.9 (d, J PC ) 10 Hz,
2
COD), 98.8 (d, J PC ) 14 Hz, COD), 95.1 (s, COD), 93.0 (s,
COD), 92.3 (bs, Ar-C(R)H-Ir), 33.2 (bs, COD), 33.1 (bs, COD),
3
3
29.7 (d, J PC ) 3 Hz, COD), 28.5 (d, J PC ) 2 Hz, COD), 26.0
(s, -CH3), 8.83 (s, -CH2-) (assignment of 1H and 13C{1H}
NMR signals were confirmed by 1H{31P} and HMQC NMR
experiments). Anal. Calcd for C30H33BF4O2PIr: C, 49.0; H, 4.5;
P, 4.2. Found: C, 49.0; H, 4.7; P, 4.3.
3
7.20 (m, 13H, Ar), 6.95 (dd, J HH ) 7.5, 4.5 Hz, 1H, Ar), 5.35
(bs, 2H, Ar-CH2-), 1.95 (q) and 1.94 (q) (3J HH ) 6.6 Hz, 2H,
(26) Giordano, G.; Crabtree, R. H. Inorg. Synth. 1990, 28, 88.
(27) Herde, J . L.; Lambert, J . C.; Senoff, C. V. Inorg. Synth. 1974,
15, 19.
(28) Schenck, T. G.; Downes, J . M.; Milne, C. R. C.; Mackenzie, P.
B.; Boucher, H.; Whelan, J .; Bosnich, B. Inorg. Chem. 1985, 24, 2334.
(29) van der Ent, A.; Onderdelinden, A. L. Inorg. Synth. 1973, 14,
92.
Rea ction of [Rh (2,5-NBD)(P P h 3)2][P F 6] w ith DP ES.
F or m a tion of [Rh H(P P h 3)2(DP ES)][P F 6] (5). A cooled (-60
°C) dihydrogen saturated solution of dichloromethane (10 mL)
was transferred by stainless steel cannula to a Schlenk tube
containing [Rh(2,5-NBD)(PPh3)2][PF6] (107 mg, 0.124 mmol)
and DPES (43.1 mg, 0.124 mmol). The solution was allowed
(30) Schrock, R. R.; Osborn, J . A. J . Am. Chem. Soc. 1976, 98, 2143.