Hexagonal Macrocycles with Trimeric Bis(terpyridine)–FeII Connectivity
tpyH), 8.77 (d, J = 5 Hz, 4 H, 6,6ЈЈ-tpyH), 8.72 (d, J = 5 Hz, 4 H,
[Fe3(8)(PF6)6] (13): A solution of FeCl2 (6.9 mg, 35 µmol) in MeOH
3,3ЈЈ-tpyH), 8.12 (s, 2 H, 2-ArH), 7.93–7.87 (m, 6 H, 4,4ЈЈ-tpyH (20 mL) was added dropwise to a solution of 8 (24 mg, 35 µmol)
and 6-ArH), 7.66 (d, J = 8 Hz, 2 H, 4-ArH), 7.54 (t, J = 8 Hz, 2 in DMF (20 mL). Following procedure GP2, the mixture was
H, 5-ArH), 7.40 (t, J = 6 Hz, 4 H, 5,5ЈЈ-tpyH), 7.12 (s, 2 H, 3,6-
ArcenterH), 4.13 (t, J = 6 Hz, 4 H, ArcenterOCH2), 1.93 (m, 4H, 34%), after work-up. H NMR (CD3CN): δ = 9.29 (s, 12 H, 3Ј,5Ј-
ArcenterOCH2CH2), 1.58 [m, 4H, ArcenterO(CH2)2CH2], 1.40–1.89 tpyH), 8.68 (m, 18 H, 3,3ЈЈ-tpyH and 2-ArH), 8.35 (d, J = 8 Hz, 6
stirred for 48 h at 50 °C to afford the deep purple solid 13 (11 mg,
1
[m, 32H, ArcenterO(CH2)3(CH2)8CH3], 0.87 [t, J = 7 Hz, 6H,
H, 6-ArH), 8.21 (s, 12 H, 2,3,5,6-ArcenterH), 8.19 (d, J = 8 Hz, 6
ArcenterO(CH2)11CH3] ppm. 13C NMR: δ = 156.39 (Ctpy2Ј), 156.27 H, 4-ArH), 8.00–7.89 (m, 18 H, 5-ArH and 4,4ЈЈ-tpyH), 7.25 (d, J
(Ctpy2), 153.93 (CAr-center2), 149.78 (Ctpy4Ј), 149.37 (Ctpy6), 139.00 = 5 Hz, 12 H, 6,6ЈЈ-tpyH), 7.13 (t, J = 6 Hz, 12 H, 5,5ЈЈ-tpyH)
(CAr3), 137.09 (Ctpy4), 132.21 (CAr6) 130.68 (CAr2), 129.19 (CAr5), ppm. 13C NMR (CD3CN): δ = 161.41 (Ctpy2Ј), 159.16 (Ctpy2),
127.42 (CAr4), 124.55 (CAr1), 124.10 (Ctpy3), 121.58 (Ctpy5), 119.09 154.14 (Ctpy6), 151.67 (Ctpy4Ј), 142.43 (CAr3), 140.64 (CAr1), 139.84
(Ctpy3Ј), 117.29 (CAr-center3), 114.17 (CAr-center1), 94.71 (CϵC- (Ctpy4), 138.95 (CAr-center1), 131.59 (CAr5), 129.97 (CAr6), 128.98
Arcenter), 86.91 (CϵC-Ar), 69.92 (CH2-O), 32.12 (CH2CH2CH3), (CAr-center2), 128.42 (Ctpy3), 128.26 (CAr2), 127.76 (CAr4), 124.99
3Ј
29.88 [CH2(CH2)9CH3], 29.84 [CH2(CH2)7CH3], 29.81 [CH2-
(CH2)6CH3], 29.64 [CH2(CH2)5CH3], 29.58 [CH2(CH2)4CH3],
(Ctpy5),
123.19
(Ctpy
)
ppm.
ESI-MS:
calcd.
for
C144H96F36Fe3N18P6 [M] 3114.4; found for [M – 3PF6]3+ 893.5, for
29.56 [CH2(CH2)3CH3], 28.30 [CH2(CH2)2CH3], 26.34 [CH2(CH2)8- [M – 4PF6]4+ 633.9, for [M – 5PF6]5+ 478.1, for [M – 5PF6
CH3], 22.89 (CH2CH3), 14.32 (CH3) ppm. ESI-MS: calcd. for PF5]5+ 452.9, and for [M – 6PF6]6+ 374.2.
C76H80N6O2 [M] 1108.6; found for [M + H]+ 1109.6 and for [M +
–
[Fe3(10)(PF6)6] (14): Following procedure GP2, a mixture of 10
(29.6 mg, 27 µmol) and FeCl2 (5.3 mg, 27 µmol) in MeOH (20 mL)
was heated at reflux for 12 h to afford the deep purple solid 14
Na]+ 1132.6. C76H80N6O2 (1109.51): calcd. C 82.27, H 7.27, N
7.57; found C 82.17, H 7.30, N 7.56.
General Procedure for the Bis(terpyridine)–FeII Macrocycle Com-
plexes (GP2): FeCl2 (1 equiv.) in MeOH was added to a stirred
solution of bis(terpyridine) (1 equiv.) in MeOH or DMF. The color
instantly changed to purple, and the mixture was heated at reflux
for 24 h under N2. After the solvent was removed in vacuo, the
residue was chromatographed on SiO2 by eluting with a H2O/
KNO3(conc.)/MeCN (1:1:10) mixture. After removal of the solvent,
the residue was washed with water, redissolved in MeOH, and ex-
cess NH4PF6 in methanol was added to precipitate the complex.
The collected dark purple solid was washed thoroughly with
MeOH to afford the desired MeCN-soluble terpyridine-FeII com-
plex.
1
(28 mg, 72%). H NMR (CD3CN): δ = 9.22 (s, 12 H, 3Ј,5Ј-tpyH),
8.65 (d, J = 8 Hz, 12 H, 3,3ЈЈ-tpyH), 8.45 (s, 6 H, 2-ArH), 8.35 (m,
6 H, 6-ArH), 7.95–7.87 (m, 24 H, 4-ArH, 4,4ЈЈ-tpyH and 5-ArH),
7.26 (s, 6 H, 3,6-ArcenterH), 7.21 (d, J = 5 Hz, 12 H, 6,6ЈЈ-tpyH),
7.12 (t, J = 6 Hz, 12 H, 5,5ЈЈ-tpyH), 4.18 (t, J = 6 Hz, 12 H,
ArcenterOCH2) ppm. 1.93 (m, 12H, ArcenterOCH2CH2), 1.70 [m,
12H, ArcenterO(CH2)2CH2], 1.46–1.06 [m, 96H, ArcenterO-
(CH2)3(CH2)8CH3], 0.86 [t, J = 6 Hz, 18H, ArcenterO(CH2)11CH3].
13C NMR (CD3CN): δ = 160.68 (Ctpy2Ј), 158.18 (Ctpy2), 154.11
(CAr-center2), 153.33 (Ctpy6), 150.04 (Ctpy4Ј), 139.12 (CAr3), 137.74
(Ctpy4), 133.24 (CAr6), 131.41 (CAr2), 130.54 (CAr5), 128.34 (CAr4),
127.71 (CAr1), 124.82 (Ctpy3), 124.21 (Ctpy5), 122.04 (Ctpy3Ј), 115.67
(CAr-center3), 114.11 (CAr-center1), 95.48 (CϵC-Arcenter), 88.43 (CϵC-
Ar), 70.95 (CH2-O), 33.05 (CH2CH2CH3), 30.77 [CH2(CH2)9CH3],
30.74 [CH2(CH2)7CH3], 30.53 [CH2(CH2)5CH3], 30.46 [CH2-
(CH2)3CH3], 27.31 [CH2(CH2)8CH3], 23.79 (CH2CH3), 14.85
(CH3) ppm. ESI-MS: calcd. for C228H240F36Fe3N18O6P6 [M]
4363.5; found for [M – 2PF6]2+ 2036.8, for [M – 3PF6]3+ 1310.2,
for [M – 3PF6 –PF5]3+ 1267.8, for [M – 3PF6 –3PF5]3+ 1183.5, for
[M – 4PF6 –2PF5]4+ 883.1, for [M – 5PF6 – PF5]5+ 702.2, and for
[M – 6PF6]6+ 582.2.
[Fe3(6)(PF6)6] (11): A solution of FeCl2 (13 mg, 65 µmol) in MeOH
(20 mL) was added dropwise to a stirred solution of 6 (39.9 mg,
65 µmol) in DMF (20 mL). Following the procedure GP2, the mix-
ture was stirred for 48 h at 50 °C to afford 11 (35 mg, 62%) as a
deep purple solid. 1H NMR (CD3CN): δ = 9.37 (s, 12 H, 3Ј,5Ј-
tpyH), 9.08 (s, 6 H, 2-ArH), 8.66 (d, J = 6 Hz, 12 H, 3,3ЈЈ-tpyH),
8.43 (d, J = 9 Hz, 6 H, 6-ArH), 8.33 (d, J = 9 Hz, 6 H, 4-ArH),
8.05 (t, J = 8 Hz, 6 H, 5-ArH), 7.83 (t, J = 6 Hz, 12 H, 4,4ЈЈ-tpyH),
7.22 (d, J = 6 Hz, 12 H, 6,6ЈЈ-tpyH), 7.04 (t, J = 6 Hz, 12 H, 5,5ЈЈ-
tpyH) ppm. 13C NMR (CD3CN): δ = 161.38 (Ctpy2Ј), 159.17
(Ctpy2), 154.16 (Ctpy6), 151.34 (Ctpy4Ј), 141.69 (CAr3), 139.61 (Ctpy4),
139.10 (CAr1), 131.63 (CAr5), 131.36 (CAr6), 129.67 (CAr2), 128.28
(CAr4), 127.97 (Ctpy3), 124.92 (Ctpy5), 123.14 (Ctpy3Ј) ppm. ESI-MS:
calcd. for C126H84F36Fe3N18P6 [M] 2886.3; found for [M – 2PF6]2+
1298.4, for [M – 3PF6]3+ 817.6, and for [M – 3PF6 – 3PF5]3+ 691.2.
C48H32N6 (692.82): calcd. C 83.21, H 4.66, N 12.13; found C 82.90,
H 4.44, N 11.67.
Acknowledgments
The authors gratefully acknowledge the National Science Founda-
tion (DMR-0401780, DMR-0705015, INT-04052803), the Air
Force Office of Scientific Research (F496200-02-1-0428,03) and the
Ohio Board of Regents for financial support.
[Fe3(7)(PF6)6] (12): Following the procedure GP2, a mixture of 7
(33 mg, 50 µmol) and FeCl2 (10.2 mg, 50 µmol) in MeOH (20 mL)
was heated at reflux for 12 h to afford 12, (44 mg, 86%) as a deep
purple solid. 1H NMR (CD3CN): δ = 9.21 (s, 12 H, 3Ј,5Ј-tpyH),
8.64 (d, J = 8 Hz, 12 H, 3,3ЈЈ-tpyH), 8.59 (s, 6 H, 2-ArH), 8.37 (d,
J = 8 Hz, 6 H, 6-ArH), 8.01 (d, J = 8 Hz, 6 H, 4-ArH), 7.94–7.85
(m, 18 H, 4,4ЈЈ-tpyH and 5-ArH), 7.20 (d, J = 5 Hz, 12 H, 6,6ЈЈ-
tpyH), 7.1 (t, J = 6 Hz, 12 H, 5,5ЈЈ-tpyH) ppm. 13C NMR
(CD3CN): δ = 161.82 (Ctpy2Ј), 159.34 (Ctpy2), 154.46 (Ctpy6), 151.09
(Ctpy4Ј), 140.17 (CAr3), 139.08 (Ctpy4), 134.55 (CAr6), 132.82 (CAr2),
131.69 (CAr5), 129.72 (CAr4), 128.77 (Ctpy3), 125.65 (CAr1), 125.37
(Ctpy5), 123.25 (Ctpy3Ј), 91.07 (CϵC) ppm. ESI-MS: calcd. for
C132H84F36Fe3N18P6 [M] 2958.3; found for [M – 5PF6]5+ 446.7, and
for [M – 6PF6]6+ 348.1.
[1] U. H. F. Bunz, Chem. Rev. 2000, 100, 1605–1644.
[2] S. Höger, J. Polym. Sci, Part A: Polym. Chem. 1999, 37, 2685–
2698.
[3] S. Höger, Chem. Eur. J. 2004, 10, 1320–1329.
[4] J. S. Moore, Acc. Chem. Res. 1997, 30, 402–413; W. Zhang, J. S.
Moore, Angew. Chem. Int. Ed. 2005, 45, 4416–4439.
[5] J. M. Tour, Chem. Rev. 1996, 96, 537–553.
[6] J. M. Tour, Acc. Chem. Res. 2000, 33, 791–804.
[7] P. J. Stang, Chem. Eur. J. 1998, 4, 19–27; H.-B. Yang, N. Das,
F. Huang, A. M. Hawkridge, D. C. Muddiman, P. J. Stang, J.
Am. Chem. Soc. 2006, 128, 10014–10015; H.-B. Yang, K.
Ghosh, N. Das, P. J. Stang, Org. Chem. 2006, 8, 3991–3994.
[8] P. N. W. Baxter, J.-M. Lehn, B. O. Kneisel, G. Baum, D. Fen-
ske, Chem. Eur. J. 1999, 5, 113–120; M. Ruben, J. Rojo, F. J.
Romero-Salguero, L. H. Uppadine, J.-M. Lehn, Angew. Chem.
Eur. J. Org. Chem. 2008, 3328–3334
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