H5) and 7.62 (d, 1H, H4). 13C NMR (CDCl3) δ Ϫ16.95 (PdMe),
17.52 (s, CH3 of iPr), 18.30 (s, CH3 of iPr), 20.62 (d, α-CH,
H5), 7.70 (d, 1H, H4) and 6.76–7.36 (m, 5H, PdC(O)Ph). 31P
NMR (CDCl ): δ 43.70 (s). IR (KBr): ν(C᎐O) 1627 cmϪ1
᎐
3
1
1JCP = 21.1), 24.10 (d, CH of iPr, JCP = 24.0 Hz), 34.90 (s,
NMe), 121.80 (s, C5) and 129.70 (s, C4). 31P NMR (CDCl3):
δ 59.46 (s).
[Pd(C(O)Me)I(P–N)] 7. This complex was prepared by the
same procedure as described for 6 by using 2 but in this case the
reaction was completed within 15 min. The complex was
obtained as a yellow powder ( 93%). Calc. for C13H24IN2OPPd:
C, 31.95; H, 4.95; N, 5.73%. Found: C, 31.54; H, 4.91; N, 6.13%.
1H NMR (CDCl3): δ 1.19–1.33 (m, 12H, CH3 of iPr), 2.23 (m,
[PdPh(PPh3)(P–N)]BF4 3. To an acetone solution (10 ml) of
the neutral complex 1 (0.5 mmol, 0.26 g), a solution containing
PPh3 (0.5 mmol, 0.13 g) and AgBF4 (0.5 mmol, 0.10 g) in
acetone (5 ml) was added slowly at 0 ЊC, resulting in immediate
silver iodide precipitation. After stirring the mixture for 40 min
the precipitate was removed by filtration and the solution
was concentrated to approximately 4–5 ml. Diethyl ether was
cautiously layered on the surface. The colorless crystals formed
were separated by filtration and dried in vacuo (0.32 g, 88%).
Calc. for PdC35H41BF4N2P2Pd: C, 56.44; H, 5.55; N, 3.76%.
Found: C, 55.97; H, 5.55; N, 3.69%. 1H NMR (CDCl3): δ 0.97–
1.31 (m, 12H, CH3 of iPr), 2.33 (m, 2H, CH of iPr), 3.42 (d, 2H,
2JPH = 8.78 Hz, PCH2), 3.82 (s, 3H, NCH3), 5.53 (d, 1H, H5),
6.57 (d, 1H, H4) and 6.64–7.44 (m, 20H, Ph). 13C NMR
(CDCl3): δ 17.09 (s, CH3 of iPr), 17.54 (s, CH3 of iPr), 19.50
2
2H, CH of iPr), 2.64 (s, 3H, PdC(O)CH3), 2.86 (d, JPH = 9.50
Hz, 2H, PCH2), 3.68 (s, 3H, NCH3), 6.83 (d, 1H, H5) and 7.34
(d, 1H, H4). 13C NMR (CDCl3): δ 17.53 (s, CH3 of iPr), 18.14
1
(s, CH3 of iPr), 19.54 (d, α-CH, JCP = 20.7), 24.08 (d, CH of
iPr, 1JCP = 20.6 Hz), 34.63 (s, NMe), 46.97 (s,CH3CO), 122.19 (s,
C5), 128.56 (s, C4) and 147.14 (s, CO). 31P NMR (CDCl3):
δ 45.57 (s). IR (KBr): ν(C᎐O) 1654 cmϪ1
.
᎐
CO insertion reactions of neutral and cationic complexes
Each organopalladium complex (1, 2, 3 and 4) was dissolved in
an appropriate solvent (0.60 ml), and CO gas (1 atm) bubbled
into the solution for 5 min at room temperature. The solution
was then vigorously shaken and subjected to NMR observation
at various intervals. The CO insertions into the M–C bonds
occurred smoothly for 1 and 2 and afforded complexes 6 and
7 respectively. On the other hand, 3 and 4 are quite stable to
CO insertion. However, a CO-coordinated complex 8 was
formed at a specific reaction condition [CO (1 atm) bubbling
for 10 min and storing the mixture at Ϫ10 ЊC for 7 d].
[PdPh(PPh3)(CO)(P–N)]BF4 8. 1H NMR (CD2Cl2): δ 0.96–
1.29 (m, 12H, CH3 of iPr), 2.32 (m, 2H, CH of iPr), 3.22 (d,
1
1
(d, α-CH, JCP = 21.7), 23.49 (d, CH of iPr, JCP = 22.3 Hz),
35.48 (s, NMe), 122.35 (s, C5), 129.52 (s, C4) and 123.07–
136.84 (m, Ph). 31P NMR (CDCl3): δ 23.85 and 49.84 (d,
2JPP = 368 Hz).
[PdMe(PPh3)(P–N)]BF4 4. This complex was prepared by the
same procedure as described for 3 by using 0.23 g of 2 (0.5
mmol), 0.10 g of AgBF4 (0.5 mmol) and 0.13 g of PPh3 (0.5
mmol). The complex was obtained as faint yellow crystals
(85%). Calc. for C30H39BF4N2P2Pd: C, 52.77; H, 5.76; N, 4.10%.
Found: C, 52.28; H, 5.84; N, 4.13%. 1H NMR (CDCl3): δ
2
2H, JPH = 10.08 Hz, PCH2), 3.75 (s, 3H, NCH3), 5.31 (d, 1H,
3
H5), 5.59 (d, 1H, H4) and 6.65–7.44 (m, 20H, Ph). 31P NMR
0.11 (dd, 3H, JPH = 4.40, PdCH3), 1.19–1.32 (m, 12H, CH3
2
2
(CD2Cl2): δ 23.78 and 49.30 (d, JPP = 367 Hz). IR (CD2Cl2):
of iPr), 2.49 (m, 2H, CH of iPr), 3.43 (d, 2H, JPH = 10.24
ν(C᎐O) 2120 cmϪ1
.
Hz, PCH2), 3.80 (s, 3H, NCH3), 5.56 (d, 1H, H5), 6.53 (d,
1H, H4) and 7.44–7.57 (m, 15H, Ph). 13C NMR (CDCl3): δ
Ϫ8.16 (PdMe), 17.70 (s, CH3 of iPr), 17.37 (s, CH3 of iPr),
᎐
Generation of [PdMe{(CD3)2CO}(P–N)]BF4 9 in an NMR tube
and its reaction with CO to give [Pd{MeC(O)}(CO)(P–N)]BF4
10
1
1
19.80 (d, α-CH, JCP = 21.5), 23.64 (d, CH of iPr, JCP = 24.0
Hz), 35.44 (s, NMe), 122.12 (s, C5), 126.80 (s, C4) and
128.88–134.73 (m, Ph). 31P NMR (CDCl3): δ 27.53 and 57.54
(d, 2JPP = 376 Hz).
To a solution containing complex 2 in acetone-d6 (0.4 ml) was
added a solution of an equimolar amount of AgBF4 in acetone-
d6 (0.3 ml) at 0 ЊC in an NMR tube. AgI was formed immedi-
ately. The NMR tube was vigorously shaken and kept until the
upper layer became clear and subjected to NMR observation.
After generating complex 9 in an NMR tube, CO was bubbled
at 0 ЊC for 3 min and NMR again observed revealing two
sets of signals which corresponded to 10 and unchanged 9.
[Pd(ꢀ3-C3H5)(P–N)]Br 5. The same procedure was used as for
the preparation of complex 1 by using 0.57 g of Pd(dba)2
(1 mmol) and 345 µl of BrC3H5 (4 mmol). The complex was
obtained as a cream-colored powder after recrystallizing from
CHCl3-Et2O (0.32 g, 73%). Calc. for C14H26BrN2PPd: C, 38.25;
1
H, 5.96; N, 6.37%. Found: C, 37.88; H, 5.81; N, 6.18%. H
1
[PdMe{(CD3)2CO}(P–N)]BF4 9. H NMR (acetone-d6): δ 0.23
(d, 3JPH = 3.9 Hz, 3H, PdCH3), 1.22–1.36 (m, 12H, CH3 of iPr),
2.48 (m, 2H, CH of iPr), 3.51 (d, 2H, PCH2), 3.81 (s, 3H,
NCH3), 6.77 (d, 1H, H5) and 7.23 (d, 1H, H4). 31P NMR
NMR (CDCl3): δ 1.18–1.26 (m, 12H, CH3 of iPr), 2.51 (m, 2H,
CH of iPr), 3.24 (br, 2H, allyl H3 and H4), 3.63 (m, 1H,
3
2
3JHH = 14.1, JPH = 9.1, allyl H2), 3.93 (d, 2H, JPH = 10.24,
PCH2), 4.07 (s, 3H, NCH3), 4.76 (m, 1H, 3JHH = 7.0, 3JPH = 6.1
Hz, allyl H1), 5.48 (m, 1H, allyl H5), 6.93 (d, 1H, H5) and 6.99
(d, 1H, H4). 13C NMR (CDCl3): δ 18.54 (s, CH3 of iPr ), 18.88
1
(acetone-d6): δ 67.26 (s). [Pd{MeC(O)}(CO)(P–N)]BF4 10. H
NMR (acetone-d6): δ 2.27 (s, 3H, PdC(O)CH3), 3.47 (d, 2H,
PCH2), 3.78 (s, 3H, NCH3), 6.73 (d, 1H, H5) and 7.21 (d, 1H,
H4). 31P NMR (acetone-d6): δ 57.14 (s). The resonances for the
protons of the isopropyl group were overlapped with those of
the respective protons of 9.
1
(s, CH3 of iPr), 21.28 (d, α-CH, JCP = 24.0), 24.72 (d, CH of
1
iPr, JCP = 23.1 Hz), 36.54 (s, NMe), 46.92 (allyl C cis to P),
76.34 (allyl C trans to P), 118.83 (CH2CHCH2), 123.04 (s, C5)
and 129.75 (s, C4). 31P NMR (CDCl3): δ 65.92 (s).
X-Ray crystallographic studies
[Pd(C(O)Ph)I(P–N)] 6. The neutral complex 1 (0.3 mmol,
0.15 g) was dissolved in chloroform (5 ml) and CO gas bubbled
into the solution for 5 min at room temperature. The solution
was then vigorously shaken and left for about 4 h. After com-
pletion of the reaction diethyl ether was layered cautiously on
the surface of the solution. The yellow crystals were separated
by filtration, washed with diethyl ether and dried in vacuo (0.16
g, 96%). Calc. for C19H26IN2OPPd: C, 39.25; H, 4.76; N, 5.09%.
Found: C, 38.83; H, 4.55; N, 5.03%. 1H NMR (CDCl3): δ 1.09–
1.15 (m, 12H, CH3 of iPr), 2.20 (m, 2H, CH of iPr), 2.84 (d,
2JPH = 9.27 Hz, 2H, PCH2), 3.64 (s, 3H, NCH3), 6.84 (d, 1H,
All crystallographic data for complexes are listed in Table 4.
Crystals of 1 were grown by slow evaporation of its chloroform
solution, those of 4 and 5 by slow diffusion of diethyl ether into
their acetone solutions. All measurements of 1 and 5 were
performed on a Rigaku AFC7R diffractometer using graphite-
monochromated Mo-Kα radiation (λ = 0.71070 Å). The meas-
urement of complex 4 was carried out by a Rigaku RAXIS-IV
imaging plate area detector using graphite monochromated
Mo-Kα radiation (λ = 0.71070 Å). The structure of 1 was
solved by Patterson methods35 whereas, those of 4 and 5 were
1096
J. Chem. Soc., Dalton Trans., 2001, 1091–1098