Organometallics
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Php), 133.4 (pst, JC−P = 6.8 Hz, Pho), 139.5 (s, C6Me5), 140.3 (s, py-4),
[Pt(PNP)(CH2CHC6Me5)](BF4)2 (5). 1H NMR (400 MHz,
3
2
140.4 (t, JC−P = 7.9 Hz, JC−Pt = 331 Hz, CH), 160.2 (pst, JC−P
=
CD2Cl2): δ 2.01 (s, 6H, CH3), 2.04 (s, 6H, CH3), 2.07 (s, 3H,
2
2
2+4
3.5 Hz, JC−Pt = 35 Hz, py-2,6). 31P NMR (101.25 MHz, CD2Cl2): δ
CH3), 4.50 (d pst, 2H, JH−H = 17.2 Hz,
J
= 4.6 Hz, PCHaHb),
H−P
1
3
3
26.4 (s, JP−Pt = 2998 Hz). MS (ESI): m/z 843 (M+).
5.05 (dt 1H, JH−H = 15.9 Hz, JH−P = 4.8 Hz, =CHaHb), 5.23 (d pst,
2
(E)-[Pt(PNP)(CHCHC6H2Me3-2,4,6)]BF4 (2). Yield: 233 mg
(75%, 0.258 mmol) Mp: 239 °C dec. Anal. Calcd for
C42H40BF4NP2Pt: C, 55.89; H, 4.47; N, 1.55. Found: C, 51.33;41 H,
2H, 2JH−H = 17.2 Hz, 2+4JH−P = 4.2 Hz, PCHaHb), 5.55 (dt, 1H, JH−H
3
2
= 7.9 Hz, JH−P < 2 Hz, JH−Pt = 73 Hz, CHaHb), 6.54 (dd, 1H,
3
3
3JH−H = 7.8 Hz, JH−H = 15.9 Hz, JH−Pt = 60 Hz, CH), 7.44−7.85
1
(m, 22H, Ph, py-3,5), 8.05 (t, 1H, JH−H = 7.8 Hz, py-4). 31P NMR
3
4.42; N, 1.45. H NMR (400 MHz, CD2Cl2): δ 1.68 (s, 6H, CH3),
2+4
1
2.14 (s, 3H, CH3), 4.56 (pst, 4H,
J
= 4.8 Hz, PCH2), 6.23 (d,
(161.98 MHz, CD2Cl2): δ 34.5 (s, JP−Pt = 2350 Hz).
H−P
1H, 3JH−H = 16.9 Hz, 3JH−Pt = 84 Hz, CH), 6.64 (s, 2H, C6H2Me3),
[Pt(PNP)(CH2CHC6H2Me3-2,4,6)](BF4)2 (6). 1H NMR (400
3
3
7.04 (dt, 1H, JH−H = 16.9 Hz, JH−P = 6.8 Hz, PtCH), 7.58−7.69
(m, 12H, Ph), 7.76 (d, 2H, 3JH−H = 7.8 Hz, py-3,5), 7.86−7.92 (m, 8H,
MHz, CD2Cl2): δ 1.99 (s, 6H, CH3), 2.17 (s, 3H, CH3), 4.55 (d pst,
2H, 2JH−H = 17.2 Hz, 2+4JH−P = 4.6 Hz, PCHaHb), 5.22 (dt 1H, 3JH−H
=
Ph), 8.07 (t, 1H, JH−H = 7.8 Hz, py-4). 13C NMR (100.61 MHz,
3
16.5 Hz, 3JH−P = 4.5 Hz, CHaHb), 5.26 (d pst, 2H, 2JH−H = 17.4 Hz,
2+4
2
3
CD2Cl2): δ 20.4 (s, p-CH3), 20.5 (s, o-CH3), 45.9 (pst, JC−P = 16.9 Hz,
J
= 4.4 Hz, PCHaHb), 5.56 (dt, 1H, JH−H = 8.0 Hz, JH−P < 2
H−P
2
1
Hz, 2JH−Pt = 70 Hz, CHaHb), 6.41 (dd, 1H, 3JH−H = 8.1 Hz, 3JH−H
=
PCH2), 120.5 (s, JC−P = 8.0 Hz, JC−Pt = 873 Hz, PtCH), 123.0
(pst, JC−P = 5.0 Hz, py-3,5), 126.8 (pst, JC−P = 29.2 Hz, Phi), 128.1 (s,
C6H2Me3), 129.6 (pst, JC−P = 5.6 Hz, Phm), 132.4 (s, Php), 133.5 (pst,
JC−P = 6.9 Hz, Pho), 134.7 (s, C6H2Me3), 134.9 (s, C6H2Me3), 137.7 (t,
3JC−P = 6.0 Hz, 2JC−Pt = 250 Hz, CH), 138.1 (s, C6H2Me3), 140.4 (s,
15.9 Hz, 3JH−Pt = 53 Hz, CH), 7.50−7.75 (m, 22H, Ph, py-3,5), 8.04
(t, 1H, JH−H = 7.8 Hz, py-4). 31P NMR (161.98 MHz, CD2Cl2): δ
3
1
34.7 (s, JP−Pt = 2339 Hz).
Preparation of (E)-[Pt(PNP)(CDCDC6Me5)]BF4 (E-1d2). Com-
plex E-1d2 was prepared according to the procedure as described
above using C2D2. Acetylene-d2 was generated by the reaction of CaC2
and D2O. 1H NMR (300 MHz, CD2Cl2): δ 1.62 (s, 6H, CH3), 2.02 (s,
6H, CH3), 2.15 (s, 3H, CH3), 4.53 (pst, 4H, 2+4JH−P = 5.0 Hz, PCH2),
2
py-4), 160.2 (pst, JC−P = 3.0 Hz, JC−Pt = 32 Hz, py-2,6). 31P NMR
(101.25 MHz, CD2Cl2): δ 26.6 (s, 1JP−Pt = 2970 Hz). MS (ESI): m/z
815 (M+).
(E)-[Pt(PNP)(CHCHC6H3Me2-2,6)]BF4 (3a) and (E)-[Pt(PNP)-
(CHCHC6H3Me2-2,4)]BF4 (3b). Complexes 3a,b were isolated as a
3/2 mixture containing 50% [Pt(PNP)(CH2CHO)]BF4 (4).27
Combined yield 3a,b: 83 mg (27%, 0.093 mmol).
3
7.55−7.90 (m, 22H, Ph, py-3,5), 8.07 (t, 1H, JH−H = 7.7 Hz, py-4).
1
31P NMR (121.49 MHz, CD2Cl2): δ 27.6 (s, JP−Pt = 2974 Hz).
Protonolysis of (E)-[Pt(PNP)(CDCDC6Me5)]BF4 (E-1d2). With
HCl. Complex E-1d2 (10 mg, 0.011 mmol) was dissolved in 0.5 mL of
CD2Cl2. To the solution was added 1 drop of concentrated HCl. After
(E)-[Pt(PNP)(CHCHC6H3Me2-2,6)]BF4 (3a). 1H NMR (400
= 4.9
H−P
2+4
MHz, CD3NO2): δ 1.71 (s, 6H, CH3), 4.55 (pst, 4H,
J
Hz, PCH2), 6.24 (d, 1H, 3JH−H = 17.1 Hz, 3JH−Pt = 81 Hz, CH), 6.80
1
mixing a H NMR spectrum was recorded.
3
3
(m, 3H, C6H3Me2), 7.13 (dt, 1H, JH−H = 17.1 Hz, JH−P = 7.2 Hz,
With HBF4·Et2O. Complex E-1d2 (100 mg, 0.107 mmol) was
dissolved in 5 mL of CH2Cl2. To the solution was added 0.1 mL (0.7
mmol) of HBF4·Et2O. The mixture was stirred overnight. The solid
products were precipitated by addition of diethyl ether. The solid was
filtered off, washed with diethyl ether, and dried under vacuum. The
3
PtCH), 7.59−7.70 (m, 12H, Ph), 7.75 (d, 2H, JH−H = 7.7 Hz, py-
3,5), 7.88−7.93 (m, 8H, Ph), 8.05 (t, 1H, JH−H = 7.7 Hz, py-4). 13C
3
NMR (100.61 MHz, CD2Cl2): δ 20.5 (s, CH3), 45.9 (pst, JC−P = 16.6
Hz, PCH2), 120.5 (s, 2JC−P = 8.0 Hz, PtCH), 123.0 (pst, JC−P = 5.0
Hz, py-3,5), 125.3 (s, C6H3Me2), 126.7 (pst, JC−P = 29.1 Hz, Phi),
127.4 (s, C6H3Me2), 129.6 (pst, JC−P = 5.5 Hz, Phm), 132.4 (s, Php),
132.5 (s, C6H3Me2), 133.4 (pst, JC−P = 6.8 Hz, Pho), 135.1 (s,
C6H3Me2), 137.6 (t, 3JC−P = 5.8 Hz, CH), 140.4 (s, py-4), 140.6 (s,
C6H3Me2), 160.2 (pst, JC−P = 3.0 Hz, py-2,6). 31P NMR (101.25 MHz,
1
solid was analyzed by H NMR spectroscopy (cf. S16 (Supporting
Information)), showing the formation of a 1/1 ratio of (E)-/(Z)-
[Pt(PNP)(CDHCDC6Me5)](BF4)2 (E/Z-5d2): 1H NMR (500
MHz, CD2Cl2): δ 1.98 (s, 6H, CH3), 2.00 (s, 6H, CH3), 2.05 (s,
2
2+4
3H, CH3), 4.37 (d pst, 2H, JH−H = 17.6 Hz,
J
= 4.5 Hz,
H−P
1
3
CD2Cl2): δ 26.4 (s, JP−Pt = 2984 Hz).
PCHaHb), 4.95 (t 0.5H, JH−P = 4.6 Hz, CHD), 5.23 (d pst, 2H,
2JH−H = 17.6 Hz, 2+4JH−P = 4.2 Hz, PCHaHb), 5.47 (dt, 0.5H, 3JH−P < 2
Hz, 2JH−Pt = 68 Hz, CHD), 7.44−7.85 (m, 22H, Ph, py-3,5), 8.05 (t,
(E)-[Pt(PNP)(CHCHC6H3Me2-2,4)]BF4 (3b). 1H NMR (400
MHz, CD3NO2): δ 1.69 (s, 3H, CH3), 2.17 (s, 3H, CH3), 4.66 (pst,
2+4
3
3
3
4H,
J
= 5.0 Hz, PCH2), 6.64 (d, 1H, JH−H = 16.7 Hz, JH−Pt =
H−P
1H, JH−H = 7.8 Hz, py-4).
75 Hz, CH), 6.80 (m, 3H, C6H3Me2), 7.55−7.70 (m, 12H, Ph),
Catalytic Hydroarylation Reaction. (a) A solution of 10 mg
(0.01 mmol) of complex 1 and 12 mg (0.08 mmol) of
pentamethylbenzene in CD2Cl2 were placed in an NMR tube. After
3
7.60 (dt, 1H, PtCH), 7.75 (d, 2H, JH−H = 7.7 Hz, py-3,5), 7.88−
3
7.93 (m, 8H, Ph), 8.05 (t, 1H, JH−H = 7.7 Hz, py-4).
1
addition of HBF4·Et2O (6 μL, 0.04 mmol) H and 31P NMR spectra
Generation of (Z)-[Pt(PNP)(CHCHAr)]BF4 (1′ and 2′).
Solutions of complex 1 and complex 2 in CD3OD, respectively,
were recorded (S18 (Supporting Information)). To the solution was
added 2.2 mL (0.09 mmol) of acetylene at 25 °C, and the progress of
catalytic conversions was monitored by NMR spectroscopy (S19 and
S20 (Supporting Information)).
(b) The experiment described in (a) was repeated using complex 5,
but this time no acid cocatalyst was added. The progress of the
catalytic reaction was followed by NMR spectroscopy (S20
(Supporting Information)).
1
were stored over 4 months at room temperature. H and 31P NMR
spectra were recorded at least 2−3 times per week over a period of 4
months.
(Z)-[Pt(PNP)(CHCHC6Me5)]BF4 (1′). 1H NMR (400 MHz,
CD2Cl2): δ 1.72 (s, 6H, CH3), 1.81 (s, 6H, CH3), 1.94 (s, 3H,
2+4
3
CH3), 4.39 (pst, 4H,
J
= 4.6 Hz, PCH2), 7.19 (d, 1H, JH−H =
H−P
3
11.8 Hz, JH−Pt = 116 Hz, CH), 7.45−7.92 (m, 22H, Ph, py-3,5),
8.05 (t, 1H, 3JH−H = 7.8 Hz, py-4), 8.27 (dt, 1H, 3JH−H = 11.8 Hz, 3JH−P
= 5.0 Hz, PtCH). 31P NMR (161.98 MHz, CD2Cl2): δ 23.4 (s,
1JP−Pt = 3038 Hz).
ASSOCIATED CONTENT
■
(Z)-[Pt(PNP)(CHCHC6H2Me3-2,4,6)]BF4 (2′). 1H NMR (400
S
* Supporting Information
Figures giving the 1H,13C COSY NMR spectrum of complex 1,
MHz, CD2Cl2): δ 1.79 (s, 6H, CH3), 2.04 (s, 3H, CH3), 4.42 (pst, 4H,
2+4
= 5.0 Hz, PCH2), 6.28 (s, 2H, C6H2Me3), 7.11 (d, 1H, 3JH−H
=
1
1H and H,1H COSY NMR spectra of the complex mixture
J
H−P
3
1
3a,b, H and 31P NMR spectra of the E−Z rearrangement of
11.9 Hz, JH−Pt = 119 Hz, CH), 7.72−7.95 (m, 22H, Ph, py-3,5),
8.19 (t, 1H, 3JH−H = 7.7 Hz, py-4), 8.30 (dt, 1H, 3JH−H = 11.9 Hz, 3JH−P
= 5.1 Hz, PtCH). 31P NMR (161.98 MHz, CD2Cl2): δ 23.3 (s,
1JP−Pt = 3023 Hz).
1
complexes 1 and 2, time-dependent H NMR spectra of E−Z
isomerization of complex 2, 1H and 31P NMR spectra of
protonolysis of complexes 1 and 2, 1H and 31P NMR spectra of
Generation of [Pt(PNP)(CH2CHAr)](BF4)2 (5 and 6). To 0.5
mL 0.01 M solutions of the complex mixtures 1/1′ and 2/2′ in
CD2Cl2, respectively, was added 1 drop (∼10 mg, ∼0.062 mmol) of
HBF4·Et2O (54% HBF4 in Et2O). 1H and 31P NMR spectra were
recorded immediately after mixing (S5, Supporting Information).
1
reaction studies with E-1d2, time-dependent H NMR spectra
for catalytic hydroarylation, conversion curves of catalytic
reactions, and mass spectra of 1 and 2, and a CIF file and table
giving crystallographic data and refinement details for
3048
dx.doi.org/10.1021/om5003123 | Organometallics 2014, 33, 3040−3050