Mononuclear Platinum(II) Complexes of a Bis-bidentate Ligand
3
3
5
3
5
7.51* (ddd, JH,H = 8.5 Hz, JH,H = 7.1 Hz, JH,H = 1.7 Hz, 1 H,
NMR (300 MHz, CD2Cl2): δ = 8.01 (dd, JH,H = 7.7 Hz, JH,H =
ArH4), 7.41* (dd, JH,H hidden, JH,H = 0.7 Hz, 1 H, ArH3), 7.35
1.6 Hz, 1 H, ArH6), 7.95 (dd, 3JH,H = 7.9 Hz, JH,H = 1.7 Hz, 1 H,
3
5
5
(“t”d, JH,H = 7.6 Hz, JH,H = 0.9 Hz, 1 H, ArH5), 7.18 (dd, JH,H ArH6), 7.82 (“t”d, JH,H = 7.7 Hz, JH,H = 1.5 Hz, 1 H, ArH4),
3
5
3
3
5
= 8.3 Hz, 5JH,H = 0.7 Hz, 1 H, ArH3), 7.07* (“t”d, 3JH,H = 7.6 Hz,
7.65 (d, JH,H = 8.4 Hz, 1 H, ArH3), 7.58 (“t”d, JH,H = 7.8 Hz,
3
3
5JH,H = 1.1 Hz, 1 H, ArH5), 3.08 [s, JH,Pt = 14.0 Hz, 3 H, 5JH,H = 1.6 Hz, 1 H, ArH4), 7.54 (“t”, 3JH,H = 7.6 Hz, 1 H, ArH5),
3
PtN(CH3)2], 2.85 [s, 3 H, N(CH3)2], 0.85 (s, JH,Pt = 94.6 Hz, 3 H, 7.24 (d, JH,H = 8.0 Hz, 1 H, ArH3), 7.12 (“t”, JH,H = 7.6 Hz, 1
2
3
3
2
PtCH3), 0.56 (s, JH,Pt = 85.5 Hz, 3 H, PtCH3).
H, ArH5), 3.20 [br. s, 3JH,Pt not resolved, 6 H, PtN(CH3)2], 2.87 [s,
3
6 H, N(CH3)2], 2.56 (s, JH,Pt = 12.9 Hz, 3 H, CH3CNPt), 1.20 (s,
[(oxanMe)2Cu4Br4] (4): CuBr (29 mg, 0.2 mmol) was added to a
mixture of 2 (62 mg, 0.2 mmol) and [Pt2(CH3)4(µ-Me2S)2] (58 mg,
0.1 mmol) in DCM (3 mL), and the solution was stirred for 0.5 h,
during which time a small quantity of yellow needles formed. The
orange solution was concentrated to ca. 1 mL and diethyl ether
(4 mL) was added slowly while stirring. Filtration, washing of the
solid with diethyl ether (3ϫ1 mL), and drying in vacuo yielded the
3JH,Pt = 80.1 Hz, 3 H, PtCH3) ppm. MS (ESI+, DCM): m/z = 559
[M]+.
[(oxanMe)PtCl2] (7): A mixture of oxanMe (594 mg, 1.94 mmol)
and [(PhCN)2PtCl2] (915 mg, 1.94 mmol) in THF (20 mL) was
heated at reflux for 68 h. After cooling to room temperature, the
precipitate was collected by filtration, washed with THF
product as a yellow powder. 1H NMR (300 MHz, CD2Cl2): δ = (3ϫ3 mL), and dried in vacuo to afford 924 mg (1.62 mmol, 83%)
8.00 (dd, JH,H = 7.9 Hz, JH,H = 1.6 Hz, 2 H, ArH6), 7.60 (ddd,
of a yellow powder. 1H NMR (300 MHz, CD2Cl2): δ = 8.04 (dd,
3
5
3JH,H = 8.4 Hz, JH,H = 7.3 Hz, JH,H = 1.7 Hz, 2 H, ArH4), 7.37
3JH,H = 7.6 Hz, JH,H = 1.7 Hz, 1 H, ArH6), 7.95 (dd, JH,H
=
3
5
5
3
(dd, JH,H = 8.4 Hz, JH,H = 0.9 Hz, 2 H, ArH3), 7.25 (ddd, JH,H
7.9 Hz, JH,H = 1.7 Hz, 1 H, ArH6), 7.77 (ddd, JH,H = 8.7 Hz,
3
5
3
5
3
= 7.9 Hz, JH,H = 7.4 Hz, JH,H = 1.1 Hz, 2 H, ArH5), 2.88 (s, 12
H, CH3) ppm. No 13C NMR could be obtained due to poor solu-
bility in DCM. C36H40Br4Cu4N8O2 (1190.56): calcd. C 36.32, H
3.39, N 9.41; found C 36.43, H 3.61, N 9.28. Crystals suitable for
XRD analysis were obtained by vapor diffusion of diethyl ether
into a dichloromethane solution of 4 at 4 °C.
3JH,H = 7.4 Hz, JH,H = 1.7 Hz, 1 H, ArH4), 7.62–7.50 (m, 3 H,
3
5
5
ArH3,4,5), 7.20 (dd, JH,H = 8.5 Hz, JH,H = 0.7 Hz, 1 H, ArH3),
3
5
3
3
5
7.08 (ddd, JH,H = 7.9 Hz, JH,H = 7.3 Hz, JH,H = 1.0 Hz 1 H,
ArH5), 3.29 [s, JH,Pt = 26.5 Hz (br. Pt satellites), 6 H, PtN(CH3)2]
3
2.90 [s, 6 H, N(CH3)2] ppm. 13C{1H} NMR (75 MHz, CD2Cl2): δ
= 165.1, 158.2, 153.8, 150.4, 135.3, 134.1, 131.7, 130.4, 128.5, 120.7,
119.5, 118.9, 116.5, 112.0 (14 CAr), 55.9 [PtN(CH3)2], 44.3
[N(CH3)2] ppm. MS (ESI+, MeCN, AgOTf): m/z = 580 [M – Cl–
+ MeCN]+. MS–MS (+580): m/z = 543 [580 – HCl], 739 [580 –
MeCN], 502 [580 – MeCN – HCl]. C18H20Cl2N4OPt (574.37):
calcd. C 37.64, H 3.51, N 9.75; found C 37.31, H 3.55, N 9.37.
Crystals suitable for XRD analysis were grown by slow concentra-
tion of a solution of 7 in MeCN (polymorph A) or by vapor dif-
fusion of diethyl ether into a solution of 7 in dichloromethane
(polymorph B).
[(oxanMe)Pt(Me)Cl] (5): This reaction was performed without pro-
tection from air. OxanMe (165 mg, 0.53 mmol) and trans-[PtMeCl-
(SMe2)2] were dissolved in THF (5 mL). The flask was placed in
an 85 °C oil bath and boiled to almost dryness (ca. 10 min) The
oily residue was dissolved again in THF (5 mL), and this cycle was
repeated 15 times. The brown residue was dissolved in DCM
(1 mL), treated with activated charcoal and filtered. Diethyl ether
(ca. 2 mL) was added until persistent turbidity of the solution. Af-
ter cooling at 4 °C for 1 h, an oily, brown precipitate was removed
from the orange solution by decantation. The solvent was evapo-
rated in vacuo, and the residue was dissolved in a minimal amount
of DCM. Diethyl ether (ca. 3 mL) was added until persistent tur-
bidity of the solution. The latter was stored at –20 °C overnight,
during which time the product crystallized. Decantation of the sol-
vent, washing with diethyl ether (3ϫ1 mL) and drying in vacuo
yielded the product as orange nodules (140 mg, 48%). An analyti-
cally pure sample was obtained by recrystallization from DCM/
octane. 1H NMR (300 MHz, CDCl3): δ = 7.92 (dd, 3JH,H = 7.7 Hz,
trans-[(oxanMe)2PtCl2] (8): After collection of 7 by filtration from
the reaction described above, the filtrate was stored at room tem-
perature for 3 d, during which time 8 crystallized as thin, pale-
yellow needles containing 2 equiv. of THF (52 mg, ca. 5%). A sol-
1
vent free sample was obtained by crystallization from MeCN. H
3
5
NMR (300 MHz, CD2Cl2): δ = 8.75 (dd, JH,H = 7.8 Hz, JH,H
=
1.6 Hz, 1 H, ArH6), 7.84 (dd, 3JH,H = 8.0 Hz, JH,H = 1.5 Hz, 1 H,
5
ArH6), 7.54 (ddd, JH,H = 8.5 Hz, JH,H = 7.3 Hz, JH,H = 1.7 Hz,
3
3
5
3
3
5
1 H, ArH4), 7.50 (ddd, JH,H = 8.4 Hz, JH,H = 7.3 Hz, JH,H
=
5JH,H = 1.6 Hz, 2 H, ArH6), 7.91 (dd, JH,H = 7.9 Hz, JH,H
=
1.7 Hz, 1 H, ArH4), 7.19 (dd, 3JH,H = 8.4 Hz, JH,H = 0.9 Hz, 1 H,
3
5
5
1.7 Hz, 2 H, ArH6), 7.68 (ddd, JH,H = 8.5 Hz, JH,H = 7.4 Hz,
ArH3), 7.09–6.95 (m, 3 H, ArH3,5,5), 2.86 [s, 6 H, N(CH3)2], 2.81
3
3
5JH,H = 1.7 Hz, 1 H, ArH4), 7.54–7.46 (m, 2 H, ArH4,5), 7.38 (“t”d, [s, 6 H, N(CH3)2] ppm. 13C{1H} NMR (75 MHz, CD2Cl2): δ =
3JH,H = 7.6 Hz, JH,H = 1.0 Hz, 1 H, ArH5), 7.16 (dd, JH,H
=
165.6, 164.9, 154.1, 153.4, 134.2, 133.9, 133.8, 131.8, 121.2, 119.8,
119.3, 117.5, 114.0, 111.9 (14 CAr), 44.6, 43.5 [2 N(CH3)2] ppm.
MS (ESI+, DCM): m/z = 883 (weak) [M + H]+, +847 [M – Cl–]+.
MS–MS (+883): m/z = 847 [883 – HCl]. MS–MS (+847): m/z =
5
3
8.4 Hz, JH,H = 0.9 Hz, 1 H, ArH3), 7.06 (ddd, JH,H = 7.9 Hz,
5
3
3JH,H = 7.3 Hz, JH,H = 1.1 Hz, 1 H, ArH5), 3.15 [br. s, JH,Pt not
5
3
resolved, 6 H, PtN(CH3)2], 2.87 [s, 6 H, N(CH3)2], 1.38 (s, 2JH,Pt
=
83.5 Hz, 3 H, PtCH3) ppm. 13C{1H} NMR (75 MHz, CDCl3): δ = 810 [847 – HCl]. C36H40Cl2N8O2Pt (882.75): calcd. C 48.98, H 4.57,
163.8, 158.9, 153.2, 151.2, 133.8, 133.5, 131.3, 129.4, 126.5, 120.7,
N 12.69; found C 48.69, H 4.75, N 12.52. Crystals suitable for
119.8, 118.7, 116.8, 112.7 (14 CAr), 51.0 [PtN(CH3)2], 44.3 XRD analysis were obtained by crystallization from hot MeCN.
[N(CH3)2], –22.7 (PtCH3), no JC,Pt observed ppm. C19H23ClN4OPt
[(oxanMe)Pt(OOCCH3)2] (9): A mixture of 7 (350 mg, 0.61 mmol)
and silver acetate (204 mg, 1.22 mmol) in DCM (20 mL) was
stirred for 20 h in the dark. Filtration and washing of the precipi-
tate with DCM (2ϫ2 mL) yielded a brown solution, from which
(553.95): calcd. C 41.20, H 4.18, N 10.11; found C 40.96, H 4.38,
N 10.04. Crystals suitable for XRD analysis were obtained by dis-
solving 5 in a minimal amount of DCM, adding ten volumes of
diethyl ether and letting the suspension stand for 3 d.
the solvent was removed in vacuo to yield the product as a light-
Reaction of 5 with [Cu(NCMe)4][PF6]: CD2Cl2 (0.7 mL) was added brown powder (366 mg, 96%). An analytically pure sample was
to 5 (11 mg, 20 µmol) and [Cu(NCMe)4][PF6] (7 mg, 19 µmol). Af-
ter 30 min, the yellow suspension was filtered into an NMR tube
and subjected to 1H NMR and ESI-MS analysis, which showed
that [(oxanMe)PtMe(NCMe)][PF6] (6) was cleanly formed. 1H
obtained by slow crystallization from DCM/Et2O. 1H NMR
3
5
(300 MHz, CD2Cl2): δ = 8.08 (dd, JH,H = 7.7 Hz, JH,H = 1.7 Hz,
5
1 H, ArH6), 7.90 (dd, 3JH,H = 7.9 Hz, JH,H = 1.7 Hz, 1 H, ArH6),
3
3
5
7.77 (ddd, JH,H = 8.6 Hz, JH,H = 7.4 Hz, JH,H = 1.7 Hz, 1 H,
Eur. J. Inorg. Chem. 2010, 438–446
© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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