M. Konkol, D. Steinborn / Journal of Organometallic Chemistry 691 (2006) 2839–2845
2843
FT-IR spectrometer using CsBr or KBr pellets. To run
experiments in NMR tubes, they were charged under argon
with educts and solvents by means of syringes and then
closed by melting. Reactions were performed in a shaking
machine with automatic temperature regulation. In appro-
priate time intervals NMR spectra were recorded to moni-
tor the reactions.
18H/12H, m-H, p-H/o-H of PPh3). 13C NMR (125.7
MHz, C6D6): d 1.8 (s, Si(CH3)3), 84.2 (t, J(P,C) = 2.0 Hz,
Ir@C@C), 128.0 (‘t’, m-C of PPh3), 129.9 (s, p-C of PPh3),
134.0 (‘t’, i-C of PPh3), 136.0 (‘t’, o-C of PPh3), 246.7 (t,
2J(P,C) = 10.9 Hz, Ir@C). 31P NMR (C6D6, 81 MHz): d
28.0 (s).
3
(6) Yield: 49 mg (58%). Anal. Calc. for IrClP2Si2C50H60
(1006.80): C, 59.65; H, 6.01. Found: C, 59.96; H, 6.16%.
1
3.2. Syntheses
m(C@C) 1615(s) cmꢁ1. H NMR (400 MHz, C6D6): d 0.47
(q, 12H, 3J(H,H) = 8.0 Hz, Si(CH2CH3)3), 1.05 (t, 18H,
3J(H,H) = 8.0 Hz, Si(CH2CH3)3), 7.06/7.13/7.95–8.00 (‘t’/
‘t’/m, 6H/12H/12H, p-H/m-H/o-H of PPh3). 13C NMR
(125.7 MHz, C6D6): d 7.1 (s, Si(CH2CH3)3), 9.3 (s,
Si(CH2CH3)3), 82.7 (s, br, Ir@C@C), 128.0 (‘t’, m-C of
PPh3), 129.8 (s, p-C of PPh3), 134.1 (‘t’, i-C of PPh3),
136.1 (‘t’, o-C of PPh3), 244.2 (t, 2J(P,C) = 11.0 Hz, Ir@C).
31P NMR (C6D6, 81 MHz): d 27.1 (s).
3.2.1. trans-[IrCl{@C@CR(SiR03)}(PPh3)2] (R/R0 =
Ph/Me, 2; R/R0 = Me/Me, 3; R/R0 = SiMe3/Me, 5;
R/R0 = SiEt3/Et, 6)
To a yellow suspension of [IrCl(N2)(PPh3)2] (1) (65 mg,
0.083 mmol) in benzene (2, 3) or toluene (5, 6) (2 ml), the
corresponding alkynylsilane RCBCSiR03 (2:1–2.5:1) was
added at room temperature with stirring. The reaction mix-
ture was warmed up to about 45 ꢁC and then stirred for a
few hours until a clear solution formed and a change of col-
our from yellow to red-violet (2, 3) or red-orange (5, 6)
occurred (4–6 h). The solvent volume was reduced by evap-
oration in vacuo to ca. 1 ml and freshly distilled methanol
(3:1) was added. Solvents were then evaporated in vacuo
up to 1–2 ml. The red-pink (2, 3)/orange (5, 6) precipitate
formed was subsequently filtered off, washed with metha-
nol (5 ml) at ꢁ10 ꢁC and dried in vacuo for 1 h.
3.2.2. trans-[IrCl{@C@CBn(SiMe3)}(PPh3)2] (4)
To a yellow suspension of [IrCl(N2)(PPh3)2] (1) (70 mg,
0.090 mmol) in benzene (3 ml) 1-(trimethylsilyl)-3-phenyl-
prop-1-yne (26 mg, 0.14 mmol) was added with stirring.
The reaction mixture was warmed up to about 40 ꢁC and
then stirred for a few hours until a clear solution formed
and a change of colour to deep red occurred (1–3 h). The
solvent was then removed by evaporation in vacuo to dry-
ness and freshly distilled hexane (5 ml) was added. A red-
pink precipitate was filtered off, washed with hexane
(10 ml) at ꢁ10 ꢁC and dried in vacuo for 1 h. Yield:
(2) Yield: 60 mg (78%). Anal. Calc. for IrClP2SiC47H44
(926.57): C, 60.93; H, 4.79. Found: C, 59.72; H, 5.22%.
m(C@C) 1587(s) cmꢁ1 1H NMR (400 MHz, C6D6): d
.
ꢁ0.04 (s, 9H, Si(CH3)3), 6.76/6.89 (‘t’/‘t’,1 1H/2H, p-H/
m-H of Ph), 6.97–7.00/7.91–7.96 (m/m, 18H/13H, p-H,
m-H of PPh3/o-H of PPh3, o-H of Ph). 13C NMR
(100 MHz, C6D6): d 0.8 (s, Si(CH3)3), 101.6 (m, Ir@C@C),
121.9 (s, i-C of Ph), 124.2 (s, p-C of Ph), 127.5 (s, o-C or m-
C of Ph, the other one is overlapped with C6D6/PPh3),
128.1 (‘t’, m-C of PPh3), 130.2 (s, p-C of PPh3), 132.7 (‘t’,
i-C of PPh3), 135.8 (‘t’, o-C of PPh3), 263.5 (t,
2J(P,C) = 12.9 Hz, Ir@C). 31P NMR (81 MHz, C6D6): d
25.1 (s).
45 mg (53%). m(C@C) 1659 (m, br) cmꢁ1 1H NMR
.
(500 MHz CD2Cl2,): d ꢁ0.58 (s, 9H, Si(CH3)3), 3.22 (s,
2H, CH2), 6.70/6.90/6.96 (‘d’/‘t’/‘t’, 2H/2H/1H, o-H/m-
H/p-H of Ph), 7.36–7.42/7.67–7.71 (m/m, 18H/12H, m-H,
p-H/o-H of PPh3). 13C NMR (CD2Cl2, 125.7 MHz): d
ꢁ0.8 (s, Si(CH3)3), 16.8 (s, CH2), 95.5 (t, 3J(P,C) = 3.6 Hz,
Ir@C@C), 125.8 (s, p-C of Ph), 127.7/129.2 (s/s, m-C and o-
C of Ph), 128.2 (‘t’, m-C of PPh3), 130.3 (s, p-C of PPh3),
133.3 (‘t’, i-C of PPh3), 135.8 (‘t’, o-C of PPh3), 142.6 (s,
2
i-C of Ph), 256.1 (t, J(P,C) = 12.6 Hz, Ir@C). 31P NMR
(3) Yield: 40 mg (56%). Anal. Calc. for IrClP2SiC42H42
(864.50): C, 58.35; H, 4.90. Found: C, 57.98; H, 5.32%.
(CD2Cl2, 81 MHz): d 25.2 (s).
m(C@C) 1652(w) cmꢁ1
.
1H NMR (400 MHz, C6D6): d
3.2.3. Formation of trans-[IrCl{@C@CiPr(SiMe3)}-
(PPh3)2] (7)
In an NMR tube [IrCl(N2)(PPh3)2] (1) (30 mg,
0.038 mmol) and 3-methyl-1-(trimethylsilyl)but-1-yne
(13 mg, 0.09 mmol) were reacted in C6D6 (1 ml) at room
temperature for a few hours until a yellow suspension
turned to a deep red solution. 1H NMR (400 MHz,
ꢁ0.29 (s, 9H, Si(CH3)3), 1.55 (t, 3H, 5J(P,H) = 2.1 Hz,
CH3), 7.01–7.10/7.93–7.98 (m/m, 18H/12H, p-H, m-H/o-
H of PPh3). 13C NMR (125.7 MHz, C6D6): d ꢁ6.1 (s,
CH3), ꢁ1.3 (s, Si(CH3)3), 88.4 (t, 3J(P,C) = 3.6 Hz,
Ir@C@C), 127.9 (‘t’, m-C of PPh3), 129.9 (s, p-C of
PPh3), 133.4 (‘t’, i-C of PPh3), 135.9 (‘t’, o-C of PPh3),
257.9 (t, 2J(P,C) = 13.1 Hz, Ir@C). 31P NMR (81 MHz,
C6D6): d 25.8 (s).
C6D6):
d
ꢁ0.04 (s, 9H, Si(CH3)3), 0.62 (d, 6H,
3J(H,H) = 6.7 Hz, CH3), 2.47 (m, 1H, CH), 7.02–7.12/
7.95–8.00 (m/m, 18H/12H, m-H, p-H/o-H of PPh3). 13C
NMR (125.7 MHz, C6D6): d 0.8 (s, Si(CH3)3), 14.6 (s,
(5) Yield: 48 mg (62%). Anal. Calc. for IrClP2Si2C44H48
(922.64): C, 57.28; H, 5.24. Found: C, 57.38; H, 5.39%.
1
3
m(C@C) 1639 (s, br) cmꢁ1. H NMR (400 MHz, C6D6): d
CH), 25.0 (s, CH3), 102.4 (t, J(P,C) = 3.1 Hz, Ir@C@C),
ꢁ0.06 (s, 18H, Si(CH3)3), 7.02–7.15/7.96–8.00 (m/m,
128.1 (‘t’, m-C of PPh3), 129.9 (s, p-C of PPh3), 133.6 (‘t’,
i-C of PPh3), 136.0 (‘t’, o-C of PPh3), 258.0 (t,
2J(P,C) = 12.4 Hz, Ir@C). 31P NMR (81 MHz, C6D6): d
25.0 (s).
1
Here and in the following ‘t’ denotes pseudotriplet, ‘d’ pseudodoublet.