(CH Instruments). Experiments were performed in a small
volume (1 mL) electrochemical cell (Cypress systems) using a
three-electrode arrangement. This consisted of a 1 mm diameter
glassy carbon (GC) disk electrode (Cypress systems), a platinum
wire auxiliary electrode and a silver wire quasi-reference
electrode. Potentials were referenced to the formal potential
of the ferrocene/ferrocenium couple measured in situ. The
solvent electrolyte system consisted of 0.1 M tetra-n-butyl-
ammonium hexafluorophosphate (TBAPF6) (Aldrich, electro-
chemical grade) in freshly distilled acetonitrile or anhydrous
dichloromethane. All scans were conducted at 0.2 V sꢂ1 and
carried out at ambient temperature (20 ꢃ 2 1C). All solutions
were deoxygenated using grade 5 nitrogen prior to electro-
chemical experimentation. The GC working electrode was
polished prior to each experiment using a Buehler Microcloths
polishing cloth with an aqueous slurry of 0.3 mm alumina.
All reagents were purchased from Aldrich and used as
received. 1H and 13C NMR spectra were recorded on a Bruker
Avance 400 MHz NMR spectrometer. Chemical shifts are
reported in parts per million (ppm) relative to the residual
27.2, 22.9, 22.8, 14.3, 14.2. IR (cmꢂ1): 3065, 2960, 2925, 2877,
2209, 1714, 1679, 1569, 1427, 1319, 1230, 1214, 762, 719, 687.
HR-MS (ESI, +ve, DCM/MeOH) m/z: calcd 679.3342, found
679.3347 [M + H]+.
3c: Brown solid, 93% yield. C44H50N2O6; Mp: 245–247 1C.
1H NMR (400 MHz, CDCl3, TMS): d 8.64 (s, 2H), 7.52 (d,
J = 6.69 Hz, 4H), 7.11 (d, J = 6.54 Hz, 4H), 4.11 (t, J = 6.9 Hz,
4H), 3.90 (s, 6H), 1.66 (m, 4H), 1.29 (br, m, 20H), 0.86 (t, J =
7.0 Hz, 6H). 13C NMR (125 MHz, CDCl3): d 162.8, 160.1,
154.1, 149.5, 141.5, 136.3, 132.8, 129.9, 127.4, 125.6, 122.8,
56.0, 31.9, 29.5, 29.4, 27.3, 22.8, 14.2. IR (cmꢂ1): 3062, 2968,
2919, 2872, 2210, 1714, 1668, 1559, 1419, 1327, 1219, 767, 713,
686. HR-MS (ESI, +ve, DCM/MeOH) m/z: calcd 703.3742,
found 703.3739 [M + H]+.
3d: Gray solid, 94% yield. C44H46N2O6; Mp: 228–229 1C.
1H NMR (400 MHz, CDCl3, TMS): d 10.14 (s, 2H), 8.63
(s, 2H), 8.07 (d, J = 8.4 Hz, 4H), 7.54 (d, J = 8.2 Hz, 4H),
4.13 (t, J = 6.8 Hz, 4H), 1.66 (m, 4H), 1.24 (br, m, 20H), 0.85
(t, J = 6.8 Hz, 6H). 13C NMR (125 MHz, CDCl3): d 191.8,
162.3, 162.2, 146.8, 146.6, 136.2, 135.2, 134.9, 134.9, 134.8,
130.8, 129.9, 128.9, 128.4, 128.2, 128.1, 127.6, 126.1, 123.4,
41.3, 31.9, 29.4, 29.3, 27.2, 22.8, 14.2. IR (cmꢂ1): 3062, 2968,
2919, 2872, 2210, 1739, 1717, 1668, 1562, 1417, 1327, 1217,
771, 716, 686. HR-MS (ESI, +ve, DCM/MeOH) m/z: calcd
699.3429, found 699.3423 [M + H]+.
1
CHCl3 peak (7.26 ppm in the H NMR and 79.43 ppm in the
13C NMR) and coupling constants (J) are reported in Hertz
(Hz). Matrix-assisted laser desorption ionisation (MALDI)
time-of-flight (TOF) mass spectra were recorded on
Bruker-Dalton Reflex III mass spectrometer.
a
3e: Light yellow solid, 97% yield. C46H54N2O4; Mp:
218–220 1C. 1H NMR (300 MHz, CDCl3, TMS): d 8.62
(s, 2H), 7.12 (s, 2H), 7.01 (s, 4H), 4.05 (t, J = 6.8 Hz, 4H),
2.37 (s, 12H), 1.61 (m, 4H), 1.26 (br, m, 20H), 0.86 (t, J = 7.0 Hz,
6H). 13C NMR (75 MHz, CDCl3): d 162.8, 162.5, 148.2, 140.8,
138.1, 135.9, 125.9, 125.6, 31.9, 29.9, 29.5, 29.4, 27.2, 22.8,
21.6, 14.2. IR (cmꢂ1): 3063, 2960, 2924, 2879, 2205, 1715,
1681, 1578, 1430, 1319, 1229, 1220, 761, 723, 689. HR-MS
(ESI, +ve, DCM/MeOH) m/z: calcd 699.4156, found
699.4134 [M + H]+.
Typical experimental procedure
A mixture of aqueous 2 M Na2CO3 (1 mL) and dioxane
(3 mL) was repeatedly degassed by purging with argon gas, and
into it the boronic acid (3 mmol) and N,N0-di-(n-octyl)-2,6-
dibromo-1,4,5,8-naphthalenetetracarboxylic acid diimide 2a
or N,N0-di-(n-octyl)-2,6-dicholoro-1,4,5,8-naphthalenetetra-
carboxylic acid diimide 2b (1 mmol) along with 2 mol% of
Pd(PPh3)4 was added. The mixture was heated in an argon
atmosphere under the complete exclusion of light for 12 h,
after which it was quenched with the addition of 10% aqueous
HCl. The organic layer was extracted with dichloromethane,
washed consecutively with water and brine before being
dried over MgSO4 and concentrated. The crude product was
then chromatographed over flash silica gel, with DCM–hexane
(2 : 1) as eluent to afford core-substituted NDIs (3a–3i).
3a: Brown solid, 97% yield. C44H50N2O4; Mp: 232–233 1C.
1H NMR (400 MHz, CDCl3, TMS): d 8.64 (s, 2H), 7.28–7.36
(m, 8H), 4.24 (t, J = 6.8 Hz, 4H), 2.47 (s, 6H), 1.59–1.64
(m, 4H), 1.26 (br, m, 20H), 0.86 (t, J = 6.8 Hz, 6H). 13C NMR
(125 MHz, CDCl3): d 161.8, 152.7, 148.7, 143.5, 141.3, 135.7,
134.6, 133.4, 133.0, 131.6, 129.3, 127.8, 40.0, 30.9, 29.4, 29.3,
27.2, 22.7, 21.3, 14.2. IR (cmꢂ1): 3064, 2969, 2918, 2869, 2214,
1717, 1676, 1560, 1418, 1331, 1216, 769, 715, 689. HR-MS
(ESI, +ve, DCM/MeOH) m/z: calcd 671.3843, found
671.3842 [M + H]+.
3f: Gray solid, 95% yield. C46H42F12N2O4; Mp: 205–209 1C.
1H NMR (400 MHz, CDCl3, TMS): d 8.63 (s, 2H), 8.03
(s, 2H), 7.80 (s, 4H), 4.23 (t, J = 7.1 Hz, 4H), 1.64 (m, 4H),
1.26 (br, m, 20H), 0.85 (t, J = 6.8 Hz, 6H). 13C NMR
(125 MHz, CDCl3): d 161.9, 151.8, 144.7, 142.3, 135.3,
133.1, 132.4, 131.7, 128.6, 127.7, 162.8, 160.0, 154.1, 149.5,
141.5, 136.3, 132.8, 129.9, 127.4, 125.6, 122.8, 56.0, 31.9, 29.5,
29.4, 27.3, 22.8, 14.2. IR (cmꢂ1): 3062, 2968, 2919, 2872, 2210,
1714, 1668, 1559, 1419, 1327, 1219, 767, 713, 686. MALDI-
TOF m/z: calcd for C44H50N2O6 70, 126.49, 126.12, 122.49,
120.69, 41.46, 41.12, 31.93, 29.88, 29. 29, 29.13, 27.16, 22.76,
14.18. HR-MS (ESI, +ve, DCM/MeOH) m/z: calcd 915.3026,
found 915.3026 [M + H]+.
3g: Saffron-coloured solid, 86% yield. C44H46N2O6; Mp:
234–236 1C. 1H NMR (400 MHz, CDCl3, TMS): d 10.14
(s, 1H), 10.09 (s, 1H), 8.62 (s, 2H), 8.06–7.85 (m, 4H), 7.56–7.26
(s, 4H), 4.28 (t, J = 6.9 Hz, 4H), 1.71 (m, 4H), 1.24 (br, m,
20H), 0.85 (t, J = 6.9 Hz, 6H). 13C NMR (125 MHz, CDCl3):
d 190.8, 162.8, 162.2, 146.8, 146.2, 136.4, 135.2, 134.9, 134.8,
134.6, 130.5, 129.7, 128.9, 128.6, 128.3, 128.2, 127.7, 126.3,
123.9, 41.8, 31.9, 29.5, 29.4, 27.3, 22.8, 14.2. IR (cmꢂ1): 3062,
2968, 2919, 2872, 2210, 1745, 1714, 1671, 1559, 1419, 1328,
1221, 769, 717, 689. HR-MS (ESI, +ve, DCM/MeOH) m/z:
calcd 699.3429, found 699.3422 [M + H]+.
3b: Yellow solid, 96% yield. C42H44F2N2O4; Mp: 211–213 1C.
1H NMR (400 MHz, CDCl3, TMS): d 8.62 (s, 2H), 7.42
(d, J = 6.93 Hz, 4H), 7.25 (d, J = 6.73 Hz, 4H), 4.07
(t, J = 6.8 Hz, 4H), 1.65 (m, 4H), 1.26 (br, m, 20H), 0.85
(t, J = 7.0 Hz, 6H). 13C NMR (125 MHz, CDCl3): d 162.5,
162.4, 146.9, 136.5, 136.4, 136.0, 130.2, 130.0, 127.5, 125.9,
123.2, 116.0, 115.6, 41.2, 32.1, 31.3, 29.9, 29.8, 29.5, 29.4, 28.2,
ꢀc
This journal is The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2009
2412 | New J. Chem., 2009, 33, 2409–2413