Iridium and rhodium complexes containing dichalcogenoimidodiphosphinato ligands

Article abstract of DOI:10.1016/j.ica.2005.10.021

Treatment of [MCl(CO)(PPh₃)₂] with K[N(R₂PQ)₂] afforded [M{N(Ph₂PQ)₂}(CO)(PPh₃)] (M = Ir, Rh; Q = S, Se). The IR C=O stretching frequencies for [M(CO)(PPh₃){N(Ph₂

Full text of DOI:10.1016/j.ica.2005.10.021

Inorganica Chimica Acta 359 (2006) 2712–2720
www.elsevier.com/locate/ica
Iridium and rhodium complexes containing
dichalcogenoimidodiphosphinato ligands
a
a
a
b
Wai-Man Cheung , Chui-Ying Lai , Qian-Feng Zhang , Wai-Yeung Wong ,
a
a,
*
Ian D. Williams , Wa-Hung Leung
a
Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, PR China
b
Department of Chemistry, Hong Kong Baptist University, Waterloo Road, Kowloon Tong, Kowloon, Hong Kong, PR China
Received 26 September 2005; accepted 17 October 2005
Available online 29 November 2005
Dedicated to Professor Brain R. James on the occasion of his 70th birthday.
Abstract
Treatment of [MCl(CO)(PPh3)2] with K[N(R2PQ)2] afforded [M{N(Ph2PQ)2}(CO)(PPh3)] (M = Ir, Rh; Q = S, Se). The IR C=O
stretching frequencies for [M(CO)(PPh3){N(Ph2PQ)2}] were found to decrease in the order S > Se. Treatment of [M(COD)Cl]2 with
K[N(Ph2PQ)2] afforded [M(COD){N(Ph2PQ)2}] (COD = 1,5-cyclooctadiene; M = Ir, Rh; Q = S, Se). Treatment of [Ir(ol)2Cl] with
K½NðPri2PQÞ2ꢀ afforded ½IrðolÞ2fNðPri2PQÞ2gꢀ2 (ol = cyclooctene COE, C2H4; Q = S, Se). Oxidative addition of [Ir(CO)(PPh3)-
{N(Ph2PS)2}] and [Ir(COD){N(Ph2PS)2}] with HCl afforded [Ir(H)(Cl)(CO)(PPh3){N(Ph2PS)2}] and trans-[Ir(H)(Cl)(COD)-
{N(Ph2PS)2}], respectively. Oxidative addition of [Ir(CO)(PPh3){N(Ph2PS)2}] with MeI afforded [Ir(Me)(I)(CO)(PPh3){N(Ph2PS)2}].
Treatment of [Ir(COE)2Cl]2 with K[N(R2PO)2] afforded [Ir(COE)2{N(Ph2PO)2}] that reacted with MeOTf (OTf = triflate) to give
[Ir{N(Ph2PO)2}(COE)2(Me)(OTf)]. The crystal structures of [Ir(CO)(PPh3){N(Ph2PS)2}], [M(COD){N(Ph2PS)2}] (M = Ir, Rh),
½IrðolÞ fNðPr2i PSÞ gꢀ(ol = COE, C2H4), trans-[Ir(H)(Cl)(COD){N(Ph2PS)2}], and [Ir(COE)2{N(Ph2PO)2}] have been determined.
2
2
Ó 2005 Elsevier B.V. All rights reserved.
Keywords: Iridium; Rhodium; Chalcogen ligands; Crystal structures; Oxidative addition
1. Introduction
well explored. The only structurally characterized Ir and
Rh dichalcogenoimidodiphosphinates are the half-sand-
wich complexes [Cp*M{N(R2PQ)2}X] [9–11]. Previously,
The coordination chemistry of dichalcogenoimido-
diphosphinates [N(R2PQ)2]ꢁ (Q = S, Se, Scheme 1) has
received increasing attention due to recent reports on con-
venient syntheses of these ligands [1–6]. Bidentate
[N(R2PQ)2]ꢁ can be considered as the chalcogen analogues
of acetylacetonate (acac). A range of main group and tran-
sition metal ions with [N(R2PQ)2]ꢁ have been synthesized.
Metal complexes with [N(R2PQ)2]ꢁ have been used as cat-
alysts for organic reactions [7] and NMR shift reagents [8].
Despite the high affinity of [N(R2PQ)2]ꢁ for late transition
metal ions, their complexes with Ir and Rh have not been
we
have
demonstrated
that
the
unsaturated
[RuII{N(R2PS)2}2] core can stabilize a variety of reactive
species including sulfur monoxide [12], diazene [13], car-
bene, and vinylidene [14]. To further explore the organo-
metallic chemistry of dichalcogenoimidodiphosphinates,
we sought to synthesize Ir and Rh compounds with
[N(R2PQ)2]ꢁ ligands. Also of interest are organoiridium
compounds containing [N(R2PO)2]ꢁ due to a recent report
that Ir compounds with O-donor ligands, notably acetyl-
acetonate, can catalyze anti-Markovnikov hydroarylation
of olefins [15]. We here describe the syntheses and crystal
structures of Ir and Rh dichalcogenoimidodiphosphinate
compounds containing carbonyl, 1,5-cyclooctadiene, and
*
Corresponding author. Tel.: +852 2358 7360; fax: +852 2358 1594.
E-mail address: chleung@ust.hk (W.-H. Leung).
0020-1693/$ - see front matter Ó 2005 Elsevier B.V. All rights reserved.
doi:10.1016/j.ica.2005.10.021

W.-M. Cheung et al. / Inorganica Chimica Acta 359 (2006) 2712–2720
2713
Ph
N
d = 7.27–8.06 (m, 35H, Ph) ppm. 31P{1H} NMR
(121.5 MHz, CDCl3): d = 18.26 (dd, J = 10.3, 23.5 Hz,
PPh3), 33.26 (d, J = 23.0, 2.4 Hz), 33.95 (t, J = 10.3,
2.4 Hz) ppm. IR (KBr, cmꢁ1): 1952 [m(CO)].
Ph
M
Ir
Ir Se
Rh S
Q
S
P
P
Q
CO
1
2
3
4
M
M
Ir
Rh Se
Q
PPh3
M = Ir, Q = Se (2): Yield: 76 mg, 53%. Anal. Calc for
C43H35IrNOP3Se2 Æ CH2Cl2: C, 47.6; H, 3.4; N, 1.3. Found:
Ph
Ph
Ph
M(CO)Cl(PPh3)
1
C, 47.9; H, 3.5; N, 1.0%. H NMR (300 MHz, CDCl3):
d = 7.28–8.07 (m, 35H, Ph) ppm. 31P{1H} NMR
(121.5 MHz, CDCl3): d = 18.19 (dd, J = 29.4, 10.2 Hz,
PPh3), 21.85 (d, J = 29.4 Hz), 23.45 (d, J = 10.2 Hz)
ppm. IR (KBr, cmꢁ1): 1946 [m(CO)].
Ph
M
Ir
Ir Se
Rh S
Q
S
K
N
P
P
Q
5
6
7
Q
P
Q
P
N
R
R
R
[M(COD)Cl]2
Q
Ir
O
15
R
M = Rh, Q = S (3): Yield: 84 mg, 71%. Anal. Calc. for
C43H35NOP3RhS2 Æ CH2Cl2: C, 57.0; H, 4.0; N, 1.7.
Found: C, 57.2; H, 4.0; N, 1.5%. 1H NMR (300 MHz,
CDCl3): d = 7.27–8.05 (m, Ph) ppm. 31P{1H} NMR
(121.5 MHz, CDCl3): d = 36.19 (m, PPh3), 37.84 (d,
J = 7.3, 20.1 Hz), 39.15 (dd, J = 7.3, 19.7 Hz) ppm. IR
(KBr, cmꢁ1): 1965 [m(CO)].
Ph
Pr
Ph
ol
COE
COE Se
C2H4
C2H4 Se 11
COE
C2H4
Q
S
Pr
8
9
[Ir(ol)2Cl]2
P
P
Q
ol
ol
S
10
N
O
O
16
17
Q
Pr
Pr
M = Rh, Q = Se (4): Yield: 89 mg, 68%. Anal. Calc. for
C43H35NOP3RhSe2 Æ CH2Cl2: 51.8; H, 3.8; N, 1.4. Found:
Scheme 1.
1
C, 51.6; H, 3.7; N, 1.3%. H NMR (300 MHz, CDCl3):
d = 7.31–8.04 (m, Ph) ppm. 31P{1H} NMR (121.5 MHz,
CDCl3): d = 24.50 (m, PPh3), 37.52 (m), 38.91 (m) ppm.
IR (KBr, cmꢁ1): 1958 [m(CO)].
olefin co-ligands, and their oxidative addition reactions
with MeI and HCl.
2. Experimental
2.3. Syntheses of [M(COD){N(PPh2Q)2}]
2.1. General
To a solution of [M(COD)Cl]2 (M = Rh, 148 mg; Ir,
200 mg; 0.30 mmol) in THF (15 ml) was added 2 equiva-
lents of K[N(Ph2PQ)2] (0.60 mmol), during which the color
turned from yellowish-orange to yellow immediately. The
reaction mixture was stirred at room temperature for
0.5 h. The solvent was then pumped off. Recrystallization
from hexane–Et2O–CH2Cl2 afforded yellow crystals.
M = Ir, Q = S (5): Yield: 422 mg, 94%. Anal. Calc. for
C32H32IrNP2S2 Æ CH2Cl2: C, 47.5; H, 4.1; N, 1.7. Found:
All manipulations were carried out under nitrogen by
standard Schlenk techniques. Solvents were purified, dis-
tilled and degassed prior to use. NMR spectra were recorded
on a Varian Mercury 300 spectrometer operating at 300 and
121.5 MHz for 1H and 31P, respectively. Chemical shifts (d,
ppm) were reported with reference to SiMe4 (1H) and H3PO4
(31P). Infrared spectra (KBr) were recorded on a Perkin–
Elmer 16 PC FT-IR spectrophotometer. Elemental analyses
were performed by Medac Ltd, Surrey, UK.
The ligands K[N(R2PQ)2] (R = Ph, Q = O, S [16], Se
[17], and R = Pri, Q = O, S, Se [18,19]) and the compounds
[M(CO)Cl(PPh3)2] (M = Ir, Rh [20]), [Ir(COD)Cl]2
(M = Ir, Rh [21]), and [Ir(ol)2Cl]2 (ol = cyclooctene COE
[22], C2H4 [23]) were prepared according to the literature
methods.
1
C, 47.6; H, 4.1; N, 1.7%. H NMR (300 MHz, CDCl3):
d = 1.48–1.55 (m, 2H, COD), 2.01–2.04 (m, 6H, COD),
3.76 (m, 4H, COD), 7.35–7.92 (m, 20H, Ph) ppm.
31P{1H} (121.5 MHz, CDCl3): d = 33.30 (s) ppm.
M = Ir, Q = Se (6): Yield: 246 mg, 89%. Anal. Calc. for
C32H32IrNP2Se2 Æ 1/2CH2Cl2: C, 44.1; H, 3.8; N, 1.6.
Found: C, 44.1; H, 3.9; N, 1.5%. 1H NMR (300 MHz,
CDCl3): d = 1.36–1.52 (m, 5H, COD), 1.97 (m, 3H,
COD), 3.76 (m, 4H, COD), 7.36–7.93 (m, 20H, Ph) ppm.
31P{1H} (121.5 MHz, CDCl3): d = 23.20 (s) ppm.
2.2. Syntheses of [M(CO)(PPh3){N(Ph2PQ)2}]
M = Rh, Q = S (7): Yield: 276 mg, 70%. Anal. Calc. for
C32H32NP2RhS2 Æ H2O: C, 56.7; H, 5.1; N, 2.1. Found: C,
56.8; H, 4.9; N, 2.1%. 1H NMR (300 MHz, CDCl3):
d = 1.72–1.80 (m, 4H, COD), 2.16–2.19 (m, 4H, COD), 4.19
(m, 4H, COD), 7.34–7.95 (m, 20H, Ph) ppm. 31P{1H} NMR
(121.5 MHz, CDCl3): d = 37.37 (d, JRhP = 3.0 Hz) ppm.
To a solution of [M(CO)Cl(PPh3)2] (M = Rh (97 mg), Ir
(109 mg); 0.14 mmol) in THF (15 ml) was added with 1
equivalent of K[N(Ph2PQ)2] (Q = S (68 mg), Se (84 mg);
0.14 mmol), and the reaction mixture was stirred at room
temperature overnight. The solvent was pumped off and
the residue was washed with hexane and ether. Recrystalli-
zation from CH2Cl2–Et2O afforded yellow crystals.
2.4. Syntheses of Ir(ol)2 N(PPri2Q)2
M = Ir, Q = S (1): Yield: 109 mg, 84%. Anal. Calc. for
C43H35IrNOP3S2 Æ CH2Cl2: C, 52.0; H, 3.7; N, 1.4. Found:
C, 51.9; H, 3.6; N, 1.2%. H NMR (300 MHz, CDCl3):
To a suspension of [Ir(ol)2Cl]2 (0.1 mol, L = COE
(90 mg)), C2H4 (57 mg) in Et2O (10 ml) was added 2 equiv-
1

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W.-M. Cheung et al. / Inorganica Chimica Acta 359 (2006) 2712–2720
alents of K½NðPri2PQÞ2ꢀ (0.20 mmol). The reaction mixture
was stirred at room temperature for 1 h. The solvent was
pumped off and the residue was extracted with hexane
and recrystallized from hexane at ꢁ20 °C.
from CH2Cl2–hexane to give yellow crystals. Yield:
31 mg, 57%. Anal. Calc. for C32ClH33IrNP2S2 Æ H2O: C,
1
47.8; H, 4.4; N, 1.7. Found: C, 48.0; H, 4.3; N, 1.8%. H
NMR (300 MHz, CDCl3): d = ꢁ13.6 (s, 1H, hydride),
1.65–1.85 (m, 6H, COD), 2.78–2.87 (m, 2H, COD), 4.03–
4.06 (m, 2H, COD), 4.47–4.52 (m, 2H, COD), 7.23–8.08
(m, 20H, Ph) ppm. 31P{1H} NMR (121.5 MHz, CDCl3):
d = 40.06 (s) ppm.
ol = COE, Q = S (8): Orange crystals, yield: 41 mg,
57%. Anal. Calc. for C28H56IrNP2S2: C, 46.4; H, 7.8; N,
1.9. Found: C, 46.7; H, 7.9; N, 1.9%. 1H NMR
(300 MHz, C6D6): d = 1.24 (dt, 24H, (CH3)2CH), 2.05
(sept, 4H, (CH3)2CH), 1.34–1.78 (m, 16H, COE), 2.24–
2.42 (m, 8H, COE), 2.71 (m, 4H, COE) ppm. 31P{1H}
NMR (121.5 MHz, C6D6): d = 56.79 (s) ppm.
2.7. Syntheses of [Ir(Me)(I)(CO)(PPh3){N(PPh2S)2}]
(14)
ol = COE, Q = Se (9): Red crystals, yield: 41 mg, 50%.
Anal. Calc. for C28H56IrNP2Se2: C, 41.4; H, 6.9; N, 1.7.
Found: C, 41.3; H, 6.9; N, 1.6%. 1H NMR (300 MHz,
C6D6): d = 1.46 (dt, 24 H, (CH3)2CH), 2.34 (sept, 4H,
(CH3)2CH), 1.58–1.90 (m, 16H, COE), 2.49–2.64 (m, 8H,
COE), 2.91 (m, 4H, COE) ppm. 31P{1H} NMR
(121.5 MHz, C6D6): d = 47.88 (s) ppm.
ol = C2H4, Q = S (10): Orange crystals, yield: 34 mg,
60%. Anal. Calc. for C16H36IrNP2S2: C, 34.3; H, 6.5; N,
2.5. Found: C, 34.6; H, 6.6; N, 2.5%. 1H NMR
(300 MHz, C6D6): d = 1.56 (dt, 24H, (CH3)2CH), 1.95
(sept, 4H, (CH3)2CH), 3.47 (br s, 8H, C2H4) ppm.
31P{1H} NMR (121.5 MHz, C6D6): d = 58.75 (s) ppm.
ol = C2H4, Q = Se (11): Orange crystals, yield: 38 mg,
58%. Anal. Calc. for C16H36IrNP2Se2: C, 29.4; H, 5.5; N,
2.1. Found: C, 29.6; H, 5.7; N, 2.0%. 1H NMR
(300 MHz, C6D6): d = 1.36 (dt, 24H, (CH3)2CH), 2.22
(sept, 4H, (CH3)2CH), 3.71 (br s, 8H, C2H4) ppm.
31P{1H} NMR (121.5 MHz, C6D6): d = 50.49 (s) ppm.
To a solution of 1 (85 mg, 0.09 mmol) in THF (20 ml)
was added 10 equivalents of MeI, and the reaction mixture
was stirred at room temperature overnight. The solvent was
pumped off and the residue was washed with hexane and
Et2O and recrystallized from CH2Cl2–Et2O to give yellow
crystals. Yield: 64 mg, 65%. Anal. Calc. for C44H38IIr-
NOP3S2: C, 49.2; H, 3.6; N, 1.3. Found: C, 49.0; H, 3.5;
N, 1.3%. 1H NMR (300 MHz, CDCl3): d = 1.09 (d,
3
3JPH = 4.4 Hz, CH3), 1.38 (d, JPH = 3.3 Hz, CH3), 7.14–
8.13 (m, 35H, Ph) ppm. 31P{1H} NMR (121.5 MHz,
CDCl3): d = ꢁ13.24 (m, PPh3), ꢁ10.11 (m, PPh3), 32.33
(dd, J = 4.6, 7.6 Hz), 32.69 (dd, J = 4.6, 7.6 Hz), 38.92
(m), 39.16 (m) ppm. IR (KBr, cmꢁ1): 2026 [m(CO)].
2.8. Synthesis of [Ir(COD){N(Ph2PO)2}] (15)
To a solution of [Ir(COD)Cl]2 (200 mg, 0.30 mmol) in
THF (15 ml) was added 2 equivalents of K[N(Ph2PO)2]
(200 mg, 0.60 mmol). The reaction mixture was stirred at
room temperature for 0.5 h. The solvent was then pumped
off. Recrystallization from hexane–Et2O–CH2Cl2 afforded
yellow crystals. Yield: 336 mg, 78%. Anal. Calc. For
C32H32IrNO2P2: C, 53.6; H, 4.5; N, 2.0. Found: C, 53.6;
2.5. Synthesis of [Ir(H)(Cl)(CO)(PPh3){N(Ph2PS)2}]
(12)
To a solution of 1 (50 mg, 0.05 mmol) in THF (15 ml)
was added with HCl (0.05 ml of a 1 M solution in Et2O,
0.05 mmol), and the reaction mixture was stirred at room
temperature for 90 min. The resulting colorless solution
was evaporated to dryness. Recrystallization from
CH2Cl2–hexane afforded colorless crystals. Yield: 28 mg,
58%. Anal. Calc. for C43ClH36IrNOP3S2: C, 53.4; H, 3.8;
N, 1.5. Found: C, 53.3; H, 3.8; N, 1.4%. 1H NMR
1
H, 4.5; N, 1.9%. H NMR (300 MHz, CDCl3): d = 1.31–
1.34 (m, 4H, COD), 2.20 (m, 4H, COD), 3.83 (m, 4H,
COD), 7.27–7.56 (m, 20H, Ph) ppm. 31P{1H} NMR
(121.5 MHz, CDCl3): d = 29.14 (s) ppm.
2.9. Synthesis of [Ir(COE)2{N(Ph2PO)2}] (R = Ph (16),
Pri (17))
2
(300 MHz, CDCl3): d = ꢁ17.06 (ddd, JPH = 9.0, 12 Hz,
2
1H, hydride), ꢁ13.40 (dd, JPH = 12 Hz, 1H, hydride),
These compounds were prepared similarly as for 15
using [Ir(COE)2Cl]2 in place [Ir(COD)Cl]2.
7.23–7.46 (m, 35H, Ph) ppm. 31P{1H} (121.5 MHz, CDCl3):
d = 1.57 (dd, J = 3.4, 7.8 Hz, PPh3), 2.50 (d, J = 8.9 Hz,
PPh3), 37.07 (m), 36.44 (m), 40.39 (m), 41.55 (dd, J = 6.3,
9.1 Hz) ppm. IR (KBr, cmꢁ1): 2030, 2037 [m(CO)].
16: Yield: 129 mg, 71%. Anal. Calc. for C40H48IrO2P2:
C, 58.0; H, 5.8; N, 1.7. Found: C, 57.7; H, 5.9; N, 1.6%.
1H NMR (300 MHz, C6D6): d = 1.78 (m, 16H, COE),
2.28 (m, 8H, COE), 2.48 (m, 4H, COE), 7.25 (m, 12H,
Ph), 8.22 (m, 8H, Ph) ppm. 31P{1H} NMR (121.5 MHz,
C6D6): d = 28.11 (s) ppm.
2.6. Syntheses of trans-[Ir(H)(Cl)(COD){N(PPh2S)2}]
(13)
17: Yield: 36 mg, 52%. Anal. Calc. for C28H56NO2P2Ir:
C, 48.5; H, 8.2; N, 2.0. Found: C, 48.4; H, 8.2; N, 1.9%.
1H NMR (300 MHz, C6D6): d = 1.48 (dt, 24H, (CH3)2CH),
1.65 (m, 6H, COE), 1.87–1.97 (m, 14H, COE), 2.15 (sept,
4H, (CH3)2CH), 2.40 (m, 8H, COE) ppm. 31P{1H} NMR
(121.5 MHz, C6D6): d = 53.77 (s) ppm.
To a solution of 5 (50 mg, 0.07 mmol) in THF (15 ml)
was added HCl (0.07 ml of a 1 M solution in Et2O,
0.07 mmol), and the reaction mixture was stirred at room
temperature overnight. The solvent was pumped off and
the residue was washed with hexane and recrystallization

W.-M. Cheung et al. / Inorganica Chimica Acta 359 (2006) 2712–2720
2715
Table 2
2.10. Synthesis of [Ir(COE)2{N(Ph2PO)2}(Me)(OTf)]
(18)
˚
Selected bond lengths (A) and angles (°) for [Ir(CO)(PPh3){N(Ph2PS)2}]
(1)
Ir(1)–C(25)
Ir(1)–S(2)
S(1)–P(1)
P(1)–N(1)
1.815(3)
2.4098(8)
2.031(1)
1.597(3)
Ir(1)–S(1)
Ir(1)–P(3)
S(2)–P(2)
P(2)–N(1)
2.4147(8)
2.2615(8)
2.021(1)
1.603(3)
To a solution of 16 (100 mg, 0.12 mmol) in CH2Cl2
(10 ml) was added 1 equivalent of MeOTf (15 lL,
0.13 mmol) at 0 °C. The reaction mixture was warmed to
room temperature at which it was stirred for 3 h. The
resulting pale yellow was evaporated to dryness and the
residue recrystallized from CH2Cl2–Et2O–hexane to give
pale yellow crystals. Yield: 85 mg, 71%. Anal. Calc for
C42F3H51IrNO5P2S Æ H2O: C, 49.9; H, 5.3; N, 1.4. Found:
C(25)–Ir(1)–P(3)
P(3)–Ir(1)–S(2)
P(3)–Ir(1)–S(1)
92.7(1)
176.40(3)
85.87(3)
C(25)–Ir(1)–S(2)
C(25)–Ir(1)–S(1)
S(2)–Ir(1)–S(1)
83.81(1)
177.0(1)
97.68(3)
Table 3
1
˚
Selected bond lengths (A) and angles (°) for [M(COD){N(Ph2PS)2}]
C, 49.8; H, 5.2; N, 1.4%. H NMR (300 MHz, CDCl3):
d = 7.29–7.83 (m, 20H, Ph), 2.48 (s, 3H, CH3), 2.18 (m,
4H, COE), 1.42–2.11 (m, 22H, COE) ppm. 31P{1H}
(121.5 MHz, CDCl3): d = 29.29 (s) ppm. 19F{1H} NMR
(CDCl3): d = ꢁ78.67 (s) ppm.
M = Ir (5)
M = Rh (7)
M–C(25), M–C(57)
M–C(26), M–C(58)
M–C(29), M–C(61)
M–C(30), M–C(62)
M–S(1), M–S(3)
M–S(2), M–S(4)
C(25)–C(26), C(57)–C(58)
C(29)–C(30), C(61)–C(62)
2.129(4), 2.101(5)
2.144(4), 2.150(5)
2.120(4), 2.187(6)
2.063(5), 2.162(5)
2.345(1), 2.365(1)
2.360(1), 2.350(1)
1.448(7), 1.357(8)
1.404(7), 1.412(8)
2.136(3)
2.116(3)
2.153(3)
2.141(3)
2.3745(9)
2.3890(8)
1.385(5)
1.395(5)
2.11. X-ray crystallography
A summary of crystallographic data and experimental
details for 1, 5, 7, 8, 10, 13, and 16 are summarized in Table
1. Intensity data were collected on a Bruker SMART
APEX 1000 CCD diffractometer using graphite-monochro-
C(25)–M–C(26), C(57)–M–C(58)
C(29)–M–C(30), C(61)–M–C(62)
S(1)–M–S(2), S(3)–M–S(4)
39.6(2), 37.2(2)
39.2(2), 37.9(2)
102.29(4), 101.54(4)
38.0(2)
37.9 (1)
98.48(3)
˚
mated Mo Ka radiation (k = 0.71073 A) at 100(2) K. The
collected frames were processed with the software SAINT.
Structures were solved by the direct methods and refined
by full-matrix least-squares on F2 using the SHELXTL [24]
software package. Non-hydrogen atoms were refined
anisotropically. Selected bond lengths and angles for 1, 5,
7, 8, 10, 13, and 16 are listed in Tables 2–6.
3. Results and discussion
3.1. Carbonyl phosphine complexes
The syntheses of Ir and Rh complexes with dichal-
cogenoimidodiphosphinates are summarized in Scheme 1.
Table 1
Crystallographic data and experimental details for [Ir(CO)(PPh3){N(Ph2PS)2}] Æ CH2Cl2 (1 Æ CH2Cl2), [Ir(COD){N(Ph2PS)2}] (5), [Rh(COD){N(Ph2-
PS)2}] Æ CH2Cl2 (7 Æ CH2Cl2), [Ir(COE)2{N(Pr2PS)2}] (8), [Ir(C2H4)2{N(Pr2PS)2}] (10), trans-[Ir(H)(Cl)(COD){N(Ph2PS)2}] (13), and [Ir(COE)2-
{N(Ph2PO)2}] (16)
Compound
1 Æ CH2Cl2
5
7 Æ CH2Cl2
8
10
13
16
Empirical formula
Formula weight
Crystal system
C44Cl2H37IrNOP3S2 C32H32IrNP2S2 C33Cl2H34NP2RhS2 C28H56IrNP2S2 C16H36IrNP2S2 C32ClH33IrNP2S2 C40H48IrNO2P2
1015.88
monoclinic
14.8151(8)
11.5813(7)
25.744(1)
90
102.386(1)
90
4314.3(4)
P21/c
748.85
monoclinic
14.548(1)
10.1313(8)
21.203(2)
90
109.234(1)
90
2950.7(4)
Pn
744.48
monoclinic
20.672(2)
9.2496(7)
18.986(1)
90
113.501(1)
90
3329.2(4)
P21/c
725.00
triclinic
560.72
triclinic
785.30
monoclinic
8.8265(6)
17.964(1)
18.947(1)
90
91.879(1)
90
3002.6(3)
P21/n
828.93
monoclinic
17.968(4)
13.469(3)
32.019(6)
90
105.45(3)
90
7469(3)
C2/c
˚
a (A)
10.297(1)
10.922(1)
15.071(2)
83.941(2)
71.283(2)
78.349(2)
1570.7(3)
9.4877(6)
10.0869(6)
11.8761(7)
98.990(1)°
96.266(1)
106.724(1)
1060.8(1)
˚
b (A)
˚
c (A)
a (°)
b (°)
c (°)
3
˚
V (A )
ꢀ
ꢀ
Space group
P1
P1
Z
4
4
4
2
2
4
8
Dcalc (g cmꢁ3
)
1.564
293(2)
2016
3.461
24452
1.686
293(2)
1480
4.798
16504
8211
1.485
293(2)
1520
0.919
18949
7518
1.533
100(2)
740
4.502
14192
5256
0.0212
1.756
100(2)
556
6.639
5688
3628
0.0222
1.737
293(2)
1552
4.805
17167
6731
1.474
223(2)
3344
3.694
19061
6030
0.0781
0.0526, 0.0755
0.0804, 0.0825
1.019
Temperature (K)
F(000)
l(Mo Ka) (mmꢁ1
Total reflections
Independent reflections 9626
Rint
R1a, wR2b (I > 2r(I))
R1, wR2 (all data)
Goodness-of-fitc
)
0.04
0.0189
0.0228
0.0263
0.0295, 0.0775
0.0348, 0.0805
1.063
0.021, 0.0572 0.0383, 0.1167
0.0264, 0.0614 0.0499, 0.1274
0.817
0.0206, 0.0501 0.0250, 0.0551 0.0248, 0.0685
0.0228, 0.0507 0.0267, 0.0558 0.0269, 0.0702
1.018
0.834
1.038
0.851
P
P
a
b
c
R = ( |Fo|ꢁ|Fc|)/ | Fo|.
P
P
Rw = [( w(|Fo|ꢁ|Fc|)2/ w|Fo|2)]1/2
.
P
Goodness-of-fit = [( w|Fo|ꢁ|Fc|)2/(NobsꢁNparam)]1/2
.

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W.-M. Cheung et al. / Inorganica Chimica Acta 359 (2006) 2712–2720
Table 4
i
˚
Selected bond lengths (A) and angles (°) for ½IrðolÞ2fNðPr2PQÞ2gꢀ
ol = COE (8)
ol = C2H4 (10)
Ir–C(1)
Ir–C(2)
Ir–C(11)/C(3)
Ir–C(12)/C(4)
Ir–S(1)
Ir–S(2)
C(1)–C(2)
C(11)–C(12) or C(3)–C(4)
2.161(3)
2.156(3)
2.149(3)
2.163(3)
2.3920(8)
2.3716(8)
1.422(4)
1.413(4)
2.111(5)
2.131(5)
2.130(4)
2.125(4)
2.348(1)
2.349(1)
1.396(6)
1.403(6)
C(1)–Ir(1)–C(2)
C(11)–Ir(1)–C(12) or C(3)–Ir(1)–C(4)
S(1)–Ir(1)–S(2)
38.5(1)
38.3(1)
94.99(3)
38.4(2)
38.5(2)
99.21(4)
Table 5
˚
Selected bond lengths (A) and angles (°) for trans-[Ir(H)(Cl)(COD)-
{N(Ph2PS)2}] (13)
Fig. 1. Molecular structure of [Ir(CO)(PPh3){N(Ph2PS)2}] (1).
Ir(1)–C(25)
Ir(1)–C(29)
Ir(1)–Cl(1)
Ir(1)–S(2)
P(2)–S(2)
2.202(3)
2.198(3)
2.4906(8)
2.4076(7)
2.027(1)
1.590(2)
Ir(1)–C(28)
Ir(1)–C(32)
Ir(1)–S(1)
P(1)–S(1)
2.202(3)
2.211(3)
2.3940(8)
2.033(1)
1.591(3)
ture of 1; selected bond lengths and angles are listed in
Table 2. The geometry around Ir is pseudo square planar.
Similar to other dithioimidodiphosphinate complexes, the
P(1)–N(1)
˚
P(2)–N(1)
average P–S distances in 1 (2.0266 A) is longer than that
˚
for HN(Ph2PS)2 (average 1.944 A) whereas the average
C(25)–Ir(1)–C(32)
S(1)–Ir(1)–S(2)
Cl(1)–Ir(1)–S(2)
36.7(1)
91.16(3)
79.89(3)
C(28)–Ir(1)–C(29)
Cl(1)–Ir(1)–S(1)
P(1)–N(1)–P(2)
37.0(1)
86.75(3)
134.7(2)
˚
P–N distance (1.600 A) is shorter than that of the latter
˚
(1.678 A). The two Ir–S distances are 2.4098(8) and
˚
2.4147(8) A, indicating that the difference in trans influence
between CO and PPh3, if any, is small. The Ir–C, Ir–P, and
Table 6
average Ir–S distances in 1 are 1.815(3), 2.2615(8), and
˚
˚
Selected bond lengths (A) and angles (°) for [Ir(COE)2{N(Ph2PO)2}] (16)
2.4122 A, respectively, which are similar to those in
˚
Ir–C(1)
Ir–C(11)
Ir–O(1)
N(1)–P(1)
P(1)–O(1)
C(1)–C(2)
2.105(7)
2.107(7)
2.101(4)
1.594(6)
1.534(5)
1.418(9)
Ir–C(2)
Ir–C(12)
Ir–O(2)
N(1)–P(2)
P(2)–O(2)
C(11)–C(12)
2.081(7)
2.111(7)
2.104(5)
1.606(5)
1.536(5)
1.43(1)
[Ir(CO)(PPh3)(S2CNEt2)] (1.79(1), 2.252(3), 2.378 A,
respectively) [25]. The S–Ir–S0 angle is 97.68(3)°.
3.2. 1,5-Cyclooctadiene complexes
Treatment of [Ir(COD)Cl]2 with K[N(Ph2PQ)2] afforded
[Ir(COD){N(Ph2PQ)2}] (Q = S (5), Se (6)). Similarly, the
Rh analogue [Rh(COD){N(Ph2PS)2}] (7) was prepared
from [Rh(COD)Cl]2 and K[N(Ph2PS)2]. These COD com-
pounds are air stable in both the solid state and solution.
In the 31P{1H} NMR spectra of 5 and 6, the resonances
for the [N(Ph2PQ)2]ꢁ ligands appear as singlets at
d = 33.30 and ꢁ23.20 ppm, respectively, whereas that for
C(1)–Ir(1)–C(2)
O(1)–Ir(1)–O(2)
39.6(2)
86.3(2)
C(11)–Ir(1)–C(12)
P(1)–N(1)–P(2)
39.5(3)
121.4(4)
Treatment of [Ir(CO)Cl(PPh3)2] with K[N(Ph2PQ)2]
afforded [Ir(CO)(PPh3){N(Ph2PQ)2}] (Q = S (1), Se (2)).
No reactions were found between [Ir(CO)Cl(PPh3)2] and
K[N(Ph2PO)2].
Similarly,
the
Rh
analogues
7 appears as a doublet at d = 37.37 ppm with JRhP
=
[Rh(CO)(PPh3){N(Ph2PQ)2}] (Q = S (3), Se (4)) were pre-
pared from [Rh(CO)Cl(PPh3)2] and K[N(Ph2PQ)2]. Com-
pound 1 is indefinitely stable in the solid state but
gradually air-oxidized in CH2Cl2 solution to give a Ir(III)
3.0 Hz. Complexes 5 and 7 have been characterized by X-
ray crystallography. Figs. 2 and 3 show the structures of
5 and 7; selected bond lengths are listed in Table 3. The
˚
average M–S distance in 5 (2.355 A) is slightly shorter than
peroxo
complex,
presumably
[Ir(O2)(CO)(PPh3)-
˚
˚
that in 7 (2.3818 A). The average Ir–C (2.132 A) and Rh–C
{N(Ph2PS)2}], as evidenced by the increase of m(CO) from
ca. 1952 to 2006 cmꢁ1. By comparison, the m(CO) for
[Ir(CO)(PPh3)(S2CNEt2)] and [Ir(O2)(CO)(PPh3)(S2C-
NEt2)] are 1958 and 1994 cmꢁ1, respectively [25]. For both
the Ir and Rh compounds, the IR CO stretching frequency
for the sulfido compound is higher than the selenido com-
pound, indicating that [N(Ph2PSe)2]ꢁ is a stronger donor
than [N(Ph2PS)2]ꢁ. Compound 1 has been characterized
by X-ray crystallography. Fig. 1 shows the molecular struc-
˚
(2.137 A) distances are normal for Ir(I)(COD) and Rh(I)-
(COD) complexes.
3.3. Bis-olefin complexes
Treatment of [Ir(ol)2Cl]2 (ol = COE, C2H4) with
K[N(Ph2PQ)2] afforded the bis-olefin complexes
[Ir(ol)2{N(PhPQ)2}]. However, it is difficult due to

W.-M. Cheung et al. / Inorganica Chimica Acta 359 (2006) 2712–2720
2717
tons in 8 and 9 (d = 2.71 and 2.91 ppm, respectively). The
structures of 8 and 10 have been established by X-ray crys-
tallography. Figs. 4 and 5 show the molecular structures of
8 and 10; selected bond lengths and angles are listed in
Table 4. The average Ir–C and Ir–S distances in 8 (2.157
˚
˚
and 2.3818 A, respectively) and 10 (2.124 and 2.349 A,
respectively) are similar to those in the COD analogue 5.
The S–Ir–S0 angles in 8 (94.99(3)°) and 10 (99.2(4)°) are
smaller than that in 5 (102.29(4)° and 101.54(4)°).
Fig. 2. Molecular structure of [Ir(COD){N(Ph2PS)2}] (5).
Fig. 4. Molecular structure of ½IrðCOEÞ2fNðPri2PSÞ2gꢀ (8).
Fig. 3. Molecular structure of [Rh(COD){N(Ph2PS)2}] (7).
crystallize these compounds because they are somewhat
unstable in CH2Cl2 solutions. Thus, we turned our atten-
tion to Ir complexes with ½NðPri2PQÞ2ꢀꢁ, which can be
recrystallized from hexane. Treatment of [Ir(COE)2Cl]2
and [Ir(C2H4)2Cl]2 with K½NðPri2PQÞ2ꢀ afforded hexane-
soluble ½IrðCOEÞ2fNðPri2PQÞ2gꢀ (Q = S (8), Se (9)) and
½IrðC2H4Þ2fNðPri2PQÞ2gꢀ (Q = S (10), Se (11)), respectively.
Unlike the COD analogues, these complexes are air sensi-
tive in solution. The ethylene protons in 10 and 11 appear
as broad singlets at d = 3.47 and 3.71 ppm, respectively,
which are more downfield than those for the olefinic pro-
Fig. 5. Molecular structure of ½IrðC2H4Þ fNðPri2PSÞ gꢀ (10).
2
2

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W.-M. Cheung et al. / Inorganica Chimica Acta 359 (2006) 2712–2720
3.4. Oxidative addition of Ir(I) compounds
Ph
N
Ph
Ph
N
Ph
Me
Ir
Me
Ir
P
P
S
CO
P
P
S
I
Treatment of 1 with HCl afforded the Ir(III) hydrido
chloro compound [Ir(H)(Cl)(CO)(PPh3){N(Ph2PS)}] (12),
which was isolated as a ca. 3:2 mixture of two isomers
according to 1H NMR spectroscopy. The IR spectrum
shows two CO bands at 2030 and 2037 cmꢁ1, which are
comparable to that in [Ir(Me)(I)(CO)(PPh3)(S2CNEt2)]
(2025 cmꢁ1) [25]. Despite several attempts, we were not
able to obtain single crystals for either of the two isomers.
S
S
PPh3
PPh3
I
CO
Ph
Ph
Ph
Ph
Scheme 3.
Treatment of 1 with MeI afforded the methyl com-
pounds [Ir(Me)(I)(CO)(PPh3){N(Ph2PS)}] (14), which were
isolated as a 5:1 mixture of two isomers according to NMR
1
The H NMR spectrum of 12 shows 0a doublet of doublet
00
2
of doublet at d ¼ ꢁ17:06 ð JPH ¼ 2JPH ¼ 12 Hz; 2JPH ¼ 9
HzÞ ppm and a doublet of doublet at d ¼ ꢁ13:40
spectroscopy. The IR spectrum shows m(CO) at 2026 cmꢁ1
,
0
3
ð JPH ¼ 3JPH ¼ 9 HzÞ, assignable to the hydrido ligands
which is similar to that of [Ir(Me)(I)(CO)(PPh3)(S2CNEt2)]
1
in the two isomers. Eisenberg and coworkers [25] reported
(2025 cmꢁ1) [25]. The H NMR spectrum of 14 shows two
3
3
that the JHP (cis) and JHP (trans) for [Ir(H)2(CO)-
(PPh3)(S2CNEt2)] are 10.9–20.1 and 166.5 Hz, respectively.
Thus, we believe that in each of the two isomers of 12, the
hydride is cis to PPh3 (Scheme 2).
doublets at d = 1.09 (J = 4.4 Hz) and 1.38 (J = 3.3 Hz)
ppm assignable to the methyl protons of the two isomers.
These J values are similar to that of [Ir(Me)(I)(CO)-
(PPh3)(S2CNEt2)] (3JPH = 4.1 Hz), in which the methyl
group is cis to PPh3. Thus, we believe that in each of the
two isomers of 14, the methyl group is cis to PPh3
(Scheme 3).
Treatment of 5 with HCl afforded trans-[Ir(H)(Cl)-
(COD){N(Ph2PS2)2}] (13). Unlike 12, the H NMR spec-
1
trum exhibits only one hydride signal (d = ꢁ14.3 ppm),
indicating that a single isomer was produced by the oxida-
tive addition. The solid-state structure of 13 is shown in
Fig. 6; selected bond lengths and angles are listed in Table
5. The geometry around Ir is pseudo octahedral, with the
hydride trans to the chloride. The average Ir–C distance
3.5. Ir compounds with imidodiphosphinates
Treatment of [Ir(COD)Cl]2 with K[N(Ph2PO)2] afforded
[Ir(COD){N(R2PO)2}] (15). Similarly, [Ir(COE)2{N(R2-
PO)2}] (R = Ph (16), Pri (17)) were prepared from
[Ir(COE)2Cl]2 and K[N(R2PO)2]. No reaction was found
between [Ir(CO)Cl(PPh3)2] and K[N(R2PO)2]. To our
knowledge, 15–17 are the first Ir compounds with imi-
dodiphosphinato ligands. These compounds are stable in
the solid state but air sensitive in solutions. The 31P reso-
nances for the imidodiphosphinate ligands were observed
at d = 28.11 and 53.77 ppm, respectively, which are more
downfield that those for K[N(R2PO)2] (d = 17.62 and
49.08 ppm for R = Ph and Pri, respectively). Compound
16 has been characterized by X-ray crystallography.
Fig. 7 shows the molecular structure of 16; selected bond
lengths and angles are listed in Table 6. The average Ir–
˚
in 13 (2.203 A) is slightly longer than that in 1 whereas
˚
the average Ir–S distance (2.4008 A) is slightly shorter than
that in 1. The S(1)–Ir–S(2) angle in 6-coordinated 13 of
91.16(3)° is smaller than that in 4-coordinated 1.
Ph
N
Ph
Ph
N
Ph
H
Ir
H
P
P
S
P
P
S
CO
Cl
Ir
S
S
PPh3
PPh3
Cl
CO
Ph
Ph
Ph
Ph
Scheme 2.
˚
˚
O (2.103 A) and Ir–O (2.101 A) distances in 16 are similar
˚
to those in [Ir(COD)(acac)] (2.042 and 2.093 A) [26]. The
O–Ir–O0 angle of 86.3(2)° is obviously smaller than the
S–Ir–S0 angle in 5. The average P–O and P–N distance
˚
(1.535 and 1.600 A, respectively) distances in 16 are compa-
rable to those in [Cu{N(Ph2PO)2}2] (1.512 and 1.578 A,
˚
respectively) [27]. The average Ir–C distance in 16
˚
(2.101 A) is slightly shorter than the sulfide analogue 8.
No reaction was found when 16 was reacted with HCl or
MeI. However, 16 underwent oxidative addition with
MeOTf to afford Ir(III) methyl compound [Ir(Me)(OTf)-
(COE)2{N(Ph2PO)2}] (18). The observations of a single
methyl resonance in the 1H NMR spectrum (d =
2.48 ppm) and a single 31P resonance (d = 29.29 ppm) indi-
cate that the oxidative addition of 16 produced a single
isomer. The 19F NMR spectrum shows a singlet at
d = ꢁ78.67 ppm due to the coordinated triflato ligand.
Fig. 6. Molecular structure of trans-[Ir(H)(Cl)(COD){N(Ph2PS)2}] (13).

W.-M. Cheung et al. / Inorganica Chimica Acta 359 (2006) 2712–2720
2719
Fig. 7. Molecular structure of [Ir(COE)2{N(Ph2PO)2}] (16).
4. Conclusions
References
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Coordination Chemistry II, vol. 1, Elsevier Pergamon, Amsterdam, p.
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Ir(I) dichalcogenoimidodiphosphinate complexes [Ir(CO)-
(PPh3){N(Ph2PQ)2}],
[Ir(COD){N(Ph2PQ)2}],
and
½IrðolÞ2fNðPri2PQÞ2gꢀ (Q = S, Se; ol = COE, C2H4). Oxi-
dative addition of these complexes has been studied.
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addition of [Ir(CO)(PPh3){N(Ph2PS)2}] with HCl and
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Ir
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imidodiphosphinate
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of [Ir(COE)2{N(Ph2PO)2}] with MeOTf afforded
[Ir(Me)(OTf)(COE)2{N(Ph2PO)2}].
5. Supplementary material
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13, and 16 have been deposited with the Cambridge
Crystallographic Data Centre as supplementary publica-
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of the data can be obtained free of charge on application
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Acknowledgements
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The financial support from the Hong Kong Research
Grants Council (Project number 602104) is gratefully
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the crystal structures.
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