Sun et al.
1249
(s, 2H, m-IMes), 6.95–7.09 (m, 12H, o-Ph (4H) + m-Ph
(4H) + p-Ph (4H)?), 7.43–7.49 (m, 4H, m-Ph), 7.80–7.87
(m, 4H, o-Ph). 13C{H} NMR d: 19.45 (Me), 21.02 (Me),
21.61 (Me), 51.11 (dd, JCP = 18, JCP = 23, PCH2P), 122.93
(NCH), 122.97 (NCH), 128.99, 129.40, 130.31, 131.70,
131.92, 133.84 (d, JCP = 20, CPhP), 133.96 (d, JCP = 16,
CPhP), 135.35, 136.69, 136.98, 137.79, 138.07, 138.33,
138.54, 193.15 (ddd, JCP = 10, JCP = 47, JCRh = 129,
Experimental section
General procedures
All manipulations were performed under an atmosphere of
dry Ar using standard Schlenk techniques or in a glove box.
Solvents (Fisher Scientific) were dried using standard proce-
dures and, before use, were purged with a stream of Ar.
C6D6 (Cambridge Isotope Laboratory) was distilled from Na
and stored under Ar. The diphosphines were used as received
from Strem Chemicals. Complexes [RhCl(COE)(IPr)]2 (1)
and [RhCl(COE)(IMes)]2 (2) were prepared by our literature
procedure.5 NMR spectra were recorded in C6D6 at room
temperature (~20 8C) either on a Bruker AV 400 or AV 300
spectrometer, data being reported in ppm relative to TMS
with the solvent signals as internal references (1H, d 7.16;
13C, d 128.38); 31P{H} NMR shifts are relative to external
85% H3PO4. J values are given in Hz (s = singlet, d =
doublet, t = triplet, spt = septet, m = multiplet, br = broad,
ps = pseudo); assignments were sometimes aided by the use
A
B
Rh–C). 31P{H} NMR: AB portion of the PA, PB, Rh
(ABX) spin system simulated by the parameters dA = –
33.57, dB = –19.93, JAB = 107.0, JAX = 102.0, JBX
=
179.0 (see text). MS (EI) (m/z): 826 [M]+, 790 [M –
HCl]+, 303 [IMes – 1]+. Anal. calcd. for C46H46N2ClP2Rh:
C 66.81, H 5.61, N 3.39; found: C 66.8, H 5.6, N 3.3.
RhCl(IPr)(Ph2PCH2CH2PPh2) (5)
Complex 5 was prepared using 50.0 mg (0.04 mmol) of 1,
31.0 mg (0.08 mmol) of dppe, and 10 mL C6H6. Yield:
1
66 mg (91%). H NMR d: 0.40 (d, 6H, J = 6.8, Me), 0.90
1
of 13C{1H}-APT and H–13C{1H}–HSQC experiments. Mass
(d, 6H, J = 6.8, Me), 1.11 (d, 6H, J = 6.8, Me), 1.42–1.64
(m, 4H, CH2-dppe), 1.68 (d, 6H, J = 6.8, Me), 3.38 (m, 2H,
CHMe2), 3.81 (m, 2H, CHMe2), 6.81 (s, 2H, NCH), 6.87 (d,
2H, J = 7.4, m-IPr), 6.93 (t, 4H, J = 7.0, m-Ph), 7.02 (t, 2H,
J = 7.0, p-Ph), 7.07–7.14 (m, 6H, o-Ph (4H) + p-Ph (2H)?),
7.26 (t, 2H, J = 7.7, p-IPr), 7.35 (d, 2H, J = 7.6, m-IPr), 7.45
spectra were obtained on a Kratos MS-50 spectrometer oper-
ating in the EI mode or on a Bruker Biflex IV spectrometer
operating with a MALDI ion source. Elemental analyses
were done on a Carlo Erba EA 1108 elemental analyzer.
RhCl(IPr)(Ph2PCH2PPh2) (3)
(t, 4H,
J = 8.5, m-Ph), 7.73–7.78 (m, 4H, o-Ph).
63.8 mg (0.05 mmol) of 1 and 38.5 mg (0.10 mmol) of
dppm were dissolved in C6H6 (6 mL). The resulting yellow
solution became orange on being stirred at room temperature
for 5 h and was then concentrated to ~2 mL; hexane
(~2 mL) was then added to precipitate the product, which
was filtered off and dried in vacuo. Yield: 85 mg (93%). H
NMR d: 0.53 (6H, d, J = 6.7, Me), 1.00 (6H, d, J = 6.7,
13C{H} NMR d: 22.90, 24.34, 27.04, 27.17, 28.90, 29.71,
32.84 (d, JCP = 25, CH2), 33.17 (d, JCP = 23, CH2), 123.90,
124.86, 124.94, 127.83, 127.92, 127.98, 128.93, 129.16,
129.75, 133.64 (d, JCP = 12, CPhP), 135.16 (d, JCP = 12,
CPhP), 136.20, 136.60, 137.94, 138.25, 144.91, 149.61,
196.72 (dd, JCP ~ 48, JCRh = 121). 31P{H} NMR d: 62.10
1
2
1
1
(dd, JPP = 38, JRhP = 123), 65.84 (2JPP = 38, JRhP = 208).
MS (EI) (m/z): 924 [M]+, 536 [M – IPr]+, 387 [IPr – 1]+.
Anal. calcd. for C53H60N2ClP2Rh: C 68.81, H 6.54, N 3.03;
found: C 68.5, H 6.4, N 3.0.
Me), 1.16 (6H, d, J = 6.7, Me), 1.89 (d, 6H, J = 6.7, Me),
3.35 (br t, 2H, J
= 9.0, J
= 8.7, PCH2P), 3.62 (spt,
HPA
HPB
2H, J = 6.7, CHMe2), 3.74 (spt, 2H, J = 6.7, CHMe2), 6.79
(s, 2H, NCH), 6.88 (ps t, 6H, m-Ph (4H) + m-IPr (2H)?),
6.96–6.99 (m, 8H, o-Ph (4H) + p-Ph (4H)?), 7.23 (t, 2H,
3JHH = 7.6, p-IPr), 7.30–7.37 (ps t, 6H, m-Ph (4H) + m-IPr
(2H)?), 7.88–7.95 (m, 4H, o-Ph). 13C{H} NMR d: 22.87,
24.36, 26.87, 27.03, 29.09, 29.69, 48.29 (dd, JCP = 19,
JCP = 30, PCH2P), 123.78, 124.52, 124.91, 128.05, 128.21,
128.31, 128.88, 129.48, 129.77, 133.01 (d, JCP = 22, CPhP),
133.96 (d, JCP = 12, CPhP), 136.35, 136.65, 136.73, 137.02,
138.13, 144.89, 149.16, 195.45 (ddd, JCP = 10, JCP = 48,
RhCl(IMes)(Ph2PCH2CH2PPh2) (6)
Complex 6 was prepared using 75.0 mg (0.07 mmol) of 2,
54.0 mg (0.14 mmol) of dppe, and 10 mL C6H6. Yield:
1
98 mg (86%). H NMR d: 1.23–1.24 (m, 4H, CH2-dppe),
1.61 (s, 6H, o-Me), 2.23 (s, 6H, o-Me), 2.79 (s, 6H, p-Me),
6.23 (s, 2H, NCH), 6.60 (s, 2H, m-IMes), 6.85 (s, 2H, m-
IMes), 6.97–7.11 and 7.04–7.08 (m, 12H, o-Ph (4H) + m-
Ph(4H) + p-Ph (4H)?), 7.51 (t, 4H, J = 8, m-Ph), 7.80 (m,
4H, o-Ph). 13C{H} NMR d: 19.72 (Me), 21.56 (Me), 21.59
(Me), 32.05 (d, JCP = 25, CH2), 32.40 (d, JCP = 25, CH2),
123.16 (NCH), 127.77, 127.86, 127.93, 128.87, 128.93,
129.01, 129.14, 130.39, 134.52 (d, JCP = 11, CPhP), 135.04
(d, JCP = 10, CPhP), 135.58, 137.57, 138.49, 138.53, 139.04,
139.36. AB portion of the PA, PB, Rh (ABX) spin system
simulated by the parameters dA = –64.26, dB = –64.96,
JAB = 36.6, JAX = 125.7, JBX = 205.7 (see text). MS (EI)
(m/z): 840 [M]+, 804 [M – HCl]+, 536 [M – IMes]+, 303
[IMes – 1]+. Anal. calcd. for C47H48N2ClP2Rh: C 67.13,
H 5.76, N 3.33; found: C 67.0, H 5.8, N 3.23.
A
B
JCRh = 128, Rh–C). 31P{H} NMR: AB portion of the PA,
PB, Rh (ABX) spin system simulated by the parameters:
dA = –35.68, dB = –20.92, JAB = 101.0, JAX = 104.0, JBX
=
178.0 (see text). MS (EI) (m/z): 910 [M]+, 387 [IPr – 1]+.
Anal calcd. for C52H58N2ClP2Rh: C 68.55, H 6.42, N 3.08;
found: C 68.8, H 6.4, N 2.9. X-ray quality crystals of 3 con-
taining 0.5 mol C6H6 solvate were grown by layering a C6H6
solution of the compound with hexane.
RhCl(IMes)(Ph2PCH2PPh2) (4)
The synthetic procedure for complexes 4–10 follows that
given for 3; here, 55.0 mg (0.05 mmol) of 2, 38.6 mg
(0.10 mmol) of dppm, and C6H6 (5 mL) were used. Yield:
RhCl(IPr)[Ph2P(CH2)4PPh2] (7)
1
74 mg (89%). H NMR d: 1.73 (s, 6H, o-Me), 2.22 (s, 6H,
Complex 7 was prepared by using 63.8 mg (0.05 mmol)
of 1, 42.7 mg (0.10 mmol) of dppb, and 10 mL C6H6. Yield:
o-Me), 2.77 (s, 6H, p-Me), 3.40 (br t, 2H, JHP = 9.1, JHP
=
8.8, PCH2P), 6.25 (s, 2H, NCH), 6.60 (s, 2H,Am-IMes), 6B.88
76 mg (80%). H NMR d: 0.59 (br s, 6H, Me), 1.05 (m,
1
Published by NRC Research Press