Job/Unit: I21208
/KAP1
Date: 24-01-13 17:49:08
Pages: 9
FULL PAPER
7.29 (m, 2 H, ArH), 7.40 (m, 9 H, ArH), 7.55 (m, 5 H, ArH),8.26 addition of thf. The product was collected by filtration and dried
(s, J = 1.9 Hz, 1 H, ArH), 8.35 (s, 1 H, ArH), 8.59 (d, J = 5.22 Hz,
1 H, ArH) ppm. 31P{1H} NMR (162 MHz, CHCl3): δ = –1.62 ppm.
ESI-MS: calcd. for [M + H]+ 453.6; found 453.3. C30H33N2P
(452.58): calcd. C 79.62, H 7.35, N 6.19; found C 78.88, H 7.67, N
6.94.
to yield 0.079 g (62%) of a yellow powder. 1H NMR (400 MHz,
CD2Cl2): δ = 0.54 (dd, 3JP,H = 17.6, 3JH,H = 7.0 Hz, 6 H, CHCH3),
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0.69 (dd, JP,H = 16.0, JH,H = 6.8 Hz, 6 H, CHCH3), 1.00–1.27
(m, 18 H, CHCH3), 2.38 (m, 2 H,CHCH3), 2.53 (m, 2 H, CHCH3),
3.99 (sept, J = 6.6 Hz, 1 H, CHCH3), 7.84–7.88 (m, 4 H, ArH),
8.23–8.38 (m, 4 H, ArH), 8.43–8.60 (m, 4 H, ArH), 8.89 (d, 2 H,
ArH) ppm. 31P{1H} NMR (162 MHz, CD2Cl2): δ = 35.18 ppm.
C37H50Cu2F12N5P4 (1043.80): calcd. C 41.95, H 4.79, N 6.79;
found C 41.95, H 5.20, N 6.52.
6-(Diisopropylphosphanyl)-2,2Ј-bipyridine (c): 6-Bromo-2,2Ј-bipyr-
idine (1.00 g, 4.25 mmol) was dissolved in Et2O (20 mL) and cooled
to –78 °C with an acetone/dry ice bath. nBuLi (1.6 m in hexanes,
2.67 mL, 4.27 mmol) was added dropwise, producing a dark-orange
solution. The solution was stirred at –78 °C for 2 h, after which a
solution of chlorodiisopropylphosphane (0.68 mL, 4.27 mmol) in
Et2O (10 mL) was added slowly to the reaction mixture. The mix-
ture was allowed to come slowly to room temperature and was
stirred at room temperature overnight. The resulting yellow solu-
tion was filtered, and the filtrate was concentrated under vacuum
to afford a bright orange oil. This was dissolved in hexanes and
filtered. The filtrate was concentrated to yield 1.12 g (96%) of a
viscous orange oil. 1H NMR (400 MHz, CDCl3): δ = 0.97 (dd, 3JP,H
= 11.8, 3JH,H = 7.0 Hz, 6 H, CHCH3), 1.15 (dd, 3JP,H = 14.5, 3JH,H
Electrochemistry: Electrochemical experiments were performed by
using a BAS Epsilon potentiostat. Cyclic voltammetry experiments
were performed under N2 or CO2 in a one-compartment cell with
a glassy carbon working electrode, a platinum wire counter elec-
trode and an Ag/AgCl reference electrode with ferrocene as an in-
ternal reference. All experiments were performed by using 0.1 m
tetrabutylammonium hexafluorophosphate (TBAH) as the sup-
porting electrolyte, acetonitrile as the solvent, and with copper
complex concentrations ranging from 0.25 to 1.0 mm.
Crystallography: Single-crystal X-ray structural data was collected
at 100 K with either a Bruker P4 or Platform, or a Kappa dif-
fractometer equipped with a Bruker Apex detector. All structures
were solved by direct methods using SHELXS-97 and refined by
full-matrix least-squares procedures using SHELXL-97.[19] Crystal-
lographic data collection and refinement information can be found
in Table S2. In complex 2, one of the hexafluorophosphate anions
showed disorder, which was modeled and refined. In 4, one of the
isopropyl groups in the bridging isocyanides showed disorder,
which was modeled and refined. CCDC-904679 (1), -904680 (2),
-904681 (3), and -904682 (4) contain the supplementary crystallo-
graphic data for this paper. These data can be obtained free of
charge from The Cambridge Crystallographic Data Centre via
www.ccdc.cam.ac.uk/data_request/cif.
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= 7.0 Hz, 6 H, CHCH3), 2.36–2.28 (septd, JP,H = 2.5, JH,H
=
7.0 Hz, 2 H, CHCH3), 7.23 (m, 1 H, ArH), 7.46 (m, 1 H, ArH),
7.69 (m, 1 H, ArH), 7.78 (m, 1 H, ArH), 8.30 (m, 1 H, ArH), 8.46
(m, 1 H, ArH), 8.64 (m, 1 H, ArH) ppm. 31P{1H} NMR
(121.5 MHz, CDCl3): δ = 15.15 ppm. ESI-MS: calcd. for [M + H]
+
273.3; found 273.1.
[Cu2(μ-PPh2-Me2-bipy)2(NCCH3)2](PF6)2 (1): A solution of 6-(di-
phenylphosphanyl)-2,2Ј-bypyridine (0.301 g, 0.860 mmol) in aceto-
nitrile (20 mL) was added to a solution of [Cu(CH3CN)4]PF6
(0.320 mg, 0.860 mol) in acetonitrile (50 mL), producing a yellow
solution, which was stirred overnight. The solvent was reduced un-
der vacuum, and Et2O was added to precipitate the product. The
solution was filtered to afford 0.296 g (58%) of 1 as a yellow solid.
1H NMR (400 MHz, CD2Cl2): δ = 1.91 (s, 6 H, CH3CN), 2.53 (s,
6 H, CH3), 2.56 (s, 6 H, CH3), 7.00–7.10 (m, 8 H, ArH), 7.16 (s, 2
H, ArH), 7.26 (d, J = 5.1 Hz, 2 H, ArH), 7.35 (t, J = 7.6 Hz, 8 H,
ArH), 7.49 (7, J = 7.5 Hz, 4 H, ArH), 7.91 (d, J = 5.3 Hz, 2 H,
ArH),8.19 (s, 2 H, ArH), 8.29 (s, 2 H, ArH) ppm. 31P{1H} NMR
(162 MHz, CD2Cl2): δ = 10.04 ppm. C52H48Cu2F12N6P4 (1235.95):
calcd. C 50.53, H 3.91, N 6.80; found C 50.59, H 3.98, N 6.64.
Supporting Information (see footnote on the first page of this arti-
cle): Additional electrochemical data and crystallographic infor-
mation for complexes 1–4.
Acknowledgments
[Cu2(μ-PPh2-tBu2-bipy)2(NCCH3)2](PF6)2 (2): Complex 2 was syn-
thesized analogously to 1 (79%). H NMR (400 MHz, CDCl3): δ
The authors would like to acknowledge the United States Air Force
Office of Scientific Research through the MURI program for fund-
ing under AFOSR Award No. FA9550-101-0572. We would also
like to thank Dr. Arnold Rheingold and Dr. Curtis Moore of the
UCSD Crystallography facility for their assistance with crystal-
lography as well as members of the Kubiak Laboratory. Special
thanks go to Eric E. Benson for his assistance with crystallography
and previous group member Dr. Sayak Roy for assistance with this
project.
1
= 1.31 (s, 18 H, CH3), 1.39 (s, 18 H, CH3), 1.88 (s, 6 H, CH3CN),
7.00–7.05 (m, 8 H, ArH), 7.19 (s, 2 H, ArH), 7.30–7.49 (m, 14 H,
ArH), 8.02 (d, J = 5.5 Hz, 2 H, ArH), 8.21 (s, 2 H, ArH), 8.28 (s, 2
H, ArH) ppm. 31P{1H} NMR (162 MHz, CD2Cl2): δ = 10.11 ppm.
C64H72Cu2F12N6P4 (1404.28): calcd. C 54.70, H 5.17, N 5.98;
found C 54.36, H 5.30, N 5.60.
[Cu2(μ-PiPr2bipy)2(μ-NCCH3)](PF6)2 (3): Complex 3 was synthe-
1
sized analogously to 1 (77%). H NMR (400 MHz, CD2Cl2): δ =
0.96–1.02 (m, 24 H, CHCH3), 2.09 (s, 3 H, NCCH3), 2.51 (m, 4 H,
CHCH3), 7.80–7.80 (m, 4 H, ArH), 8.24 (t, J = 8.1 Hz, 2 H, ArH),
8.33 (t, J = 8.1 Hz, 2 H, ArH), 8.40 (d, J = 8.1 Hz, 2 H, ArH),
8.45 (d, J = 8.3 Hz, 2 H, ArH), 8.85 (d, J = 5.2 Hz, 2 H, ArH)
δ = 34.11 ppm.
C36H48Cu2F12N6P4 (1043.78): calcd. C 41.43, H 4.64, N 5.83;
found C 39.97, H 4.76, N 6.20.
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3
[5] L. Yang, D. R. Powell, R. P. Houser, Dalton Trans. 2007, 955–
(0.130g; 0.128 mmol) was dissolved in CH2Cl2 (10 mL). Isopropyl
isocyanide (8.8 mg, 0.127 mmol) dissolved in CH2Cl2 (1 mL) was
added by syringe. The yellow solution was stirred overnight. The
solvent was reduced, and a yellow powder was precipitated by the
964.
[6] A. Bondi, J. Phys. Chem. 1964, 68, 441–452.
[7] T. C. Davenport, T. D. Tilley, Angew. Chem. 2011, 123, 12413;
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Eur. J. Inorg. Chem. 0000, 0–0
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