Organometallics
Article
resulted in full conversion to 8 after 12 h (vide infra). Data for 7 are as
follows. 1H NMR (500 MHz, C6D12): δ 0.80 (app q, 6H, CH(CH3)2, J
= 5 Hz), 0.88 (app q, 6H, CH(CH3)2, J = 5 Hz), 1.01 (app q, 6H,
CH(CH3)2, J = 10 Hz), 1.44 (app q, 6H, CH(CH3)2, J = 5 Hz), 2.20
(s, 3H, C6H4CH3), 2.33 (s, 3H, C6H4CH3), 2.50 (m, 2H, CH(CH3)2),
6.82 (m, 6H, ArH), 6.94 (m, 2H, ArH), 7.09 (m, 6H, ArH), 7.18 (dd,
2H, ArH, JHH = 5 Hz, JHP = 10 Hz), 7.25 (d, 2H, ArH, JHH = 10 Hz),
7.41 (dd, 2H, ArH, JHH = 5 Hz, JHP = 10 Hz). 13C{1H} NMR (126
MHz, C6D5CD3, −15 °C): δ 17.8 (s, CH(CH3)2), 22.0−19.0
(obscured by solvent peak, CH(CH3)2), 22.7 (app t, CH(CH3)2, JCP
= 11 Hz), 33.0 (t, CH(CH3)2, JCP = 11 Hz), 122.3 (s, ArC), 126.1 (s,
ArC), 126.3 (t, ArC, JCP = 13 Hz), 127.1 (s, ArC), 131.9 (s, ArC),
133.1 (t, ArC, JCP = 9 Hz), 134.5 (s, ArC), 135.9 (s, ArC), 141.9 (s,
ArC), 146.8 (dd, ArC, JCP = 4 Hz, JCP = 9 Hz), 155.2 (t, ArC, JCP = 15
Hz), 156.2 (t, ArC, JCP = 14 Hz, ArC), 160.2 (s, ArC), 296.4 (t, Pd
C(p-tol)2, JCP = 63 Hz). 31P{1H} NMR (200 MHz, C6D12): δ 52.4 (s).
Synthesis of 8. A benzene solution of [(PterP)Pd] (6; 54.9 mg,
0.10 mmol, 0.7 mL) and (p-tol)2CN2 (21.4 mg, 0.10 mmol) was
placed in a quartz J. Young NMR tube and exposed to UV radiation
for 5 h. The volatiles were removed under reduced pressure. The
crude residue was dissolved in 2 mL of n-pentane. [(2″-
Diisopropylphosphino-{1,1′:2′,1″-terphenyl}-2-yl)Pd(η2 -P,C-iPr2P
C(p-tol)2)] (8) crystallized at −35 °C as pale orange crystals. Yield: 40
mg, 73%. Data for 8 are as follows. 1H NMR (500 MHz, C6D6): δ 0.27
(dd, 3H, CH(CH3)2, JHH = 7 Hz, JHP = 18 Hz), 0.92 (m, 6H,
CH(CH3)2), 1.0 (dd, 3H, CH(CH3)2, JHH = 7 Hz, JHP = 15 Hz), 1.09
(dd, 3H, CH(CH3)2, JHH = 7 Hz, JHP 11 Hz), 1.17 (dd, 3H,
31P{1H} NMR spectra are consistent with the reported literature
values.79 The product, [(PCy3)2PtCl2], was used in the next step
without further purification. In a 20 mL scintillation vial, [(PCy3)PtCl2
(53.2 mg, 0.06 mmol) was dissolved in 5 mL of THF. A suspension of
KC8 (17.4 mg, 0.13 mmol) in 5 mL of THF was added to this
solution. The mixture was stirred at room temperature for 3 h. The
volatiles were removed under reduced pressure. The product was
extracted in n-pentane and filtered through a pad of Celite. The
volatiles were removed under reduced pressure and the product,
[(PCy3)2Pt], was isolated as a yellow powder. Yield: 27.0 mg, 55%.
1
The H and 31P{1H} NMR spectra are consistent with the reported
literature values.32
Reaction of [(Cy3P)2Pt] with (p-tol)2CN2. [(Cy3P)2Pt] (27.0 mg,
0.04 mmol) was dissolved in C6D6 and added to (p-tol)2CN2 (7.8 mg,
1
0.04 mmol). The mixture was monitored by H and 31P{1H} NMR
spectroscopy until full conversion of (p-tol)2CN2 to (p-tol)2CN−
NC(p-tol)2 was achieved (12 h). No conversion of [(PCy3)2Pt] was
observed. The 1H NMR spectrum for (p-tol)2CNNC(p-tol)2 is
consistent with the reported literature values.80
Reaction between [(PterP)PtC(p-tol)2] (5) and H2SiPh2. A
C6D6 solution of [(PterP)PtC(p-tol)2] (5; 28.1 mg, 0.04 mmol) was
placed in a J. Young NMR tube along with 2 equiv of Ph2SiH2 (0.02
mL, 0.08 mmol). The solution was heated to 120 °C for 3 days and
monitored by 31P{1H} NMR spectroscopy to ensure full consumption
of 5. The volatiles were removed, and the crude residue was dissolved
in n-pentane. The solution was chilled to −35 °C to induce
precipitation of [(PterP)Pt(H)SiHPh2] (9), leaving the organic
product, (di-p-tolylmethyl)diphenylsilane (69% crude NMR yield),
in the mother liquor. The final organic product was purified by column
chromatography (silica, hexanes). Data for (di-p-tolylmethyl)-
CH(CH3)2, JHH = 7 Hz, JHP = 17 Hz), 1.34 (dd, 3H, CH(CH3)2, JHH
=
7 Hz, JHP = 15 Hz), 1.52 (dd, 3H CH(CH3)2, JHH = 7 Hz, JHP = 16
Hz), 1.99 (m, 1H, CH(CH3)2), 2.11 (s, 3H, C6H4CH3), 2.16 (s, 3H,
C6H4CH3), 2.29 (m, 1H, CH(CH3)2), 2.37 (m, 1H, CH(CH3)2), 2.47
(m, 1H, CH(CH3)2), 6.80 (tt, 1H, ArH, JHH = 7 Hz, JHP = 2 Hz), 6.99
(m, 14 H, ArH), 7.32 (d, 2H, ArH, JHH = 8 Hz), 7.36 (t, 1H, ArH, JHH
= 7 Hz), 7.40 (dd, 1H, ArH, JHH = 7 Hz, JHP = 2 Hz), 7.53 (d, 2H,
ArH, JHH = 8 Hz). 13C{1H} NMR (126 Hz, C6D6): δ 18.4 (br s,
CH(CH3)2), 19.8 (d, CH(CH3)2, JCP = 7 Hz), 20.2 (d, CH(CH3)2, JCP
= 7 Hz), 20.4 (d, CH(CH3)2, JCP = 3 Hz), 20.5 (d, CH(CH3)2, JCP = 3
Hz), 20.7 (d, CH(CH3)2, JCP = 4 Hz), 21.0(s, C6H4CH3), 21.0(d,
CH(CH3)2, JCP = 14 Hz), 21.2 (s, C6H4CH3), 22.3 (d, CH(CH3)2, JCP
1
diphenylsilane are as follows. H NMR (400 MHz, CDCl3): δ 2.26
(s, 6H, C6H4CH3), 4.09 (d, 1H, CH(p-tol)2, JHH = 1 Hz), 5.18 (d, 1H,
SiHPh2, JHH = 1 Hz, JHSi = 160 Hz), 6.98 (d, 4H, ArH, JHH = 8 Hz),
7.05 (d, 4H, ArH, JHH = 8 Hz), 7.26 (m, 4 H, ArH), 7.31 (m, 6H,
ArH). 13C{1H} NMR (100 MHz, CDCl3): δ 29.9 (s, C6H4CH3), 127.9
(s, ArC), 129.2 (s, ArC), 129.2 (s, ArC), 129.7 (s, ArC), 133.5 (s,
ArC), 135.0 (s, ArC), 135.9 (s, ArC), 129.0 (s, ArC).
Synthesis of [(PterP)Pt(H)SiHPh2] (9). One equivalent of Ph2SiH2
(7.6 μL, 0.04 mmol) was added via syringe to a solution of [(PterP)Pt]
(4; 26.8 mg, 0.04 mmol) in Et2O. The mixture was stirred at room
temperature for 1 h. The volatiles were removed under reduced
pressure. The crude residue was washed with cold n-pentane, leaving 9
= 6 Hz), 22.5 (d, CH(CH3)2, JCP = 4 Hz), 23.1 (d, CH(CH3)2, JCP
=
23.7 (d, CH(CH3)2, JCP = 18 Hz), 32.3 (dd, CH(CH3)2, JCP = 13 Hz,
JCP = 10 Hz), 122.5 (s, ArC), 124.6 (dd, ArC, JCP = 6 Hz, JCP = 3 Hz),
125.3 (s, ArC), 126.3 (d, ArC, JCP = 6 Hz), 127.2 (dd, ArC, JCP = 6 Hz,
JCP = 3 Hz), 127.5 (s, ArC), 128.4 (s, ArC), 129.0 (s, ArC), 129.2 (s,
ArC), 128.8 (app t, ArC, JCP = 4 Hz), 130.9 (d, ArC, JCP = 7 Hz), 131.5
(s, ArC), 131.9 (s, ArC), 133.1 (d, ArC, JCP = 9 Hz), 134.5 (s, ArC),
134.8 (s, ArC), 136.9 (s, ArC), 140.7 (d, ArC, JCP = 3 Hz), 141.6 (d,
ArC, JCP = 4 Hz), 147.1 (dd, C(p-tol)2, JCP = 8 Hz, JCP = 4 Hz), 148.2
(d, ArC, JCP = 3 Hz), 149.2 (d, ArC, JCP = 4 Hz), 149.6 (s, ArC), 149.8
(s, ArC), 167.8 (d, ArC, JCP = 21 Hz), 168.6 (d, ArC, JCP = 21 Hz).
31P{1H} NMR (200 MHz, C6D6): δ 13.6 (d, JPP = 14 Hz), 38.2 (d, JPP
= 14 Hz). Anal. Calcd for C45H54P2Pd: C, 70.81; H, 7.13. Found: C,
70.67; H, 6.99.
X-ray Crystal Structure of 8. Single crystals were obtained as
orange blocks from a concentrated n-pentane solution at −35 °C in
the glovebox. Crystal and refinement data for 8: C45H54P2Pd; Mr =
763.22; monoclinic; space group P21/c; a = 12.1666(3) Å; b =
12.6383(3) Å; c = 25.2046(6) Å; α = 90°; β = 91.1130(10)°; γ = 90°;
V = 3874.86(16) Å3; Z = 4; T = 120(2) K; λ = 1.54178 Å; μ = 4.856
mm−1; dcalc = 1.308 g cm−3; 74785 reflections collected; 7560 unique
(Rint = 0.0424); giving R1 = 0.0250, wR2 = 0.0674 for 7051 data with I
> 2σ(I) and R1 = 0.0272, wR2 = 0.0689 for all 7560 data. Residual
electron density (e Å−3) max/min: 0.965/−0.485.
1
as a clean tan powder (31 mg, 90%). Data for 9 are as follows. H
NMR (400 MHz, C6D6): δ −3.73 (dd, 1H, PtH, JHP = 144 Hz, JHP
=
20 Hz, JHPt = 868 Hz), 0.88 (m, 4H, CH(CH3)2), 1.04 (m, 14H,
CH(CH3)2), 1.24 (m, 6H, CH(CH3)2), 2.44 (m, 3H, CH(CH3)2),
3.21 (m, 1H, CH(CH3)2), 5.10 (m, 1H, SiH), 6.85 (m, 6H, ArH), 6.92
(t, 1H, ArH, JHH = 8 Hz), 7.0 (t, 1H, ArH, JHH = 8 Hz), 7.07 (m, 3H,
ArH), 7.18 (m, 2H, ArH), 7.30 (t, 3H, ArH, JHH = 8 Hz), 7.39 (t, 2H,
ArH, JHH = 8 Hz), 7.98 (d, 2H, ArH, JHH = 8 Hz), 8.07 (d, 2H, ArH,
JHH = 8 Hz). 13C{1H} NMR (100 MHz, C6D6): δ 17.8 (br s,
CH(CH3)2), 18.4 (br s, CH(CH3)2), 20.0 (s, CH(CH3)2), 20.1 (s,
CH(CH3)2), 20.4 (s, CH(CH3)2), 20.2 (s, CH(CH3)2), 22.4 (br m,
CH(CH3)2), 22.3 (d, CH(CH3)2, JCP = 11 Hz), 26.7 (br d, CH(CH3)2,
JCP = 23 Hz), 27.9 (d, CH(CH3)2, JCP = 14 H), 28.1 (d, CH(CH3)2,
JCP = 13 Hz), 33.9 (br d, CH(CH3)2, JCP = 23 Hz), 126.1 (s, ArC),
126.7 (s, ArC), 127.1 (s, ArC), 127.2 (s, ArC), 27.3 (s, ArC), 127.6 (s,
ArC), 126.7 (s, ArC), 128.1 (ArC, obscured by solvent peaks), 129.5
(s, ArC), 130.1 (s, ArC), 130.8 (br s, ArC), 132.9 (d, ArC, JCP = 7 Hz),
133.5 (d, ArC, JCP = 7 Hz), 136.6 (s, ArC, JCPt = 30 Hz), 137.8 (s, ArC,
JCPt = 34 Hz), 140.8 (s, ArC), 141.5 (s, ArC), 146.2 (s, ArC), 146.4 (s,
ArC), 147.3 (s, ArC), 148.2 (s, ArC). 31P{1H} NMR (162 MHz,
C6D6): δ 34.7 (unresolved d, JPPt = 2718 Hz), 40.4 (unresolved d, JPPt
Synthesis of [(Cy3P)2Pt]. To a suspension of [(COD)PtCl2] (30.0
mg, 0.08 mmol) in 5 mL of THF was added a solution of Cy3P (45.0
mg, 0.16 mmol) in 5 mL of THF. The mixture was stirred at room
temperature for 12 h. The volatiles were removed under reduced
pressure, and the residue was triturated with n-pentane (5 × 5 mL).
The residue was dried under reduced pressure. [(Cy3P)2PtCl2] was
isolated as a white powder. Yield: 53.2 mg, 80.2%. The 1H and
= 1837 Hz). 195Pt {1H} NMR (C6D6, 86 MHz): δ −3644.2 (dd, JPtP
=
2750 Hz, JPtP = 1848 Hz). 29Si {1H} NMR (C6D6, 80 MHz): δ 6.6
(app d, JSiP = 149 Hz, JSiPt = 1221 Hz) Anal. Calcd for C42H52P2PtSi:
C, 59.91; H, 6.23. Found: C, 60.01; H, 6.20.
X-ray Crystal Structure of [(PterP)Pt(H)SiHPh2] (9). Single
crystals were obtained as pale yellow blocks from a concentrated n-
pentane solution at −35 °C in the glovebox. Crystal and refinement
I
Organometallics XXXX, XXX, XXX−XXX